Startin' with Scuba

June 11, 2009

A greener lake

With Folsom Lake just a few minutes away from home, I really wanted to go back there diving. And I wanted to do that as long as the lake was still full, but the weather just wasn't cooperating. This is unusual for the Sacramento area where the weather forecast usually turns to "sunny and hot" in May and stays that way until October or so. I kept checking the water level of the lake at the California Department of Water Resources website and my dive gear was packed, but I didn't get to go back to the lake until June 8, a sunny Monday morning.

The lake level was at 461 feet or just about the same as on our last dive in the lake, which means 930,000 acre-feet, close to the capacity of 975,000 acre-feet. We paid our eight dollars for a day pass and parked at Brown's Ravine with no one else there but the park cleanup crew and a couple of fishermen. The dive plan was to follow the perimeter of the submerged parking lot, then go down the boat ramp at the lot's far side until we found its bottom. We had originally planned on making and deploying some kinds of markers that would be found once the water went down again, showing how deep underwater the marker locations had been. However, we couldn't think of a good way of doing that.

The water looked quite clear from the surface, amazingly so given that there'd probably been thousands of people swimming and boating over the prior weekends. However, as soon as we waded in we saw that the color of the water had changed. It now had a distinctly greenish cast compared to the blueish tint back in mid May. It still felt clean, though, without debris or algae floating around. Water temperature at the surface was 69 degrees.

As soon as we went under I saw that the visibility was poor, probably no more than five to seven feet. There was also considerably more silt and the yellow double line on the submerged road was barely visible anymore. We had resolved to stay close together so we would not get separated, something that can happen in an instant in murky water. Visibility was so poor that at times it was hard to even follow the perimeter of the road, and I wasn't quite sure I wanted to descend down the ramp once we found it as it'd probably be like pea soup there.

One thing we noticed was that the water had warmed up quite a bit. It was 70 degrees at the surface and still 68 degree down at 25 to 30 feet, whereas it had dropped to 57 degrees at that depth just three weeks ago, with a steep drop from 70 to 57 between 15 and 20 feet. Now the temperature didn't start dropping until we got to 30 feet.

Visibility at the top of the ramp was bad, but no worse than during the 20 minutes it took to get there, and so we decided to go down. It feels a bit weird diving down a deeply submerged ramp where you can barely see anything and it gets darker and darker. The temperature also rapidly dropped into the 50s, though it didn't feel very cold with the 7mm wetsuit, hood and gloves, and having started out in fairly warm water.

We found the bottom of the boat ramp at 83 feet -- which translates to an elevation of 378 feet -- where it ended in the silt. The temperature at 83 feet was 50 degrees. I took a couple of pictures while Carol explored a few feet beyond the end of the ramp. Anything farther than that and it'd have been too easy to lose the ramp and then simply be at the murky bottom of the lake, without anything to orient yourself by.

The much lower visibility meant we saw fewer fish though they were clearly there. We did see what seemed like millions of tiny fry. First I'd thought it was just floating debris, but it was schools of little fish, everywhere.

I was surprised at how much more silt had accumulated on the bottom within just three weeks, and so we were careful not to touch bottom with our fins and stir things up. This meant staying close enough to the bottom to see where we were going, but not so close that we touched and caused silt-outs.

We made our way back up the ramp, following the steel cable in its center, and then onto the parking lot where we used the compass to cut across the lot and back to our starting point. On our prior dive the water had been clear enough to explore a bit, but this time it was just swimming in a greenish world that disappeared a few feet away from us in all directions, and all we could do was follow one another.

It was a fun dive nevertheless, and I was happy that we found the bottom of the ramp. But it was amazing to see how quickly the water had gone from fairly clear to quite green. The much higher water temperature in the top 20-25 feet probably facilitated algae growth.

The moral of the story is that if you want to dive Folsom Lake, do it as early in the year as possible, when the new water from the Sierras is still cold and fresh.

Posted by conradb212 at 02:01 PM | Comments (0)

May 29, 2009

An earthquake hits Roatan

At 3:24 in the morning, a strong earthquake, measuring 7.3 on the Richter scale, hit Roatan. According to the USGS, the epicenter was at 16.730°N, 86.209°W, less than 20 miles north off the eastern tip of Roatan. The earthquake had a shallow depth of just 10 kilometer, with shallow earthquakes usually creating greater damage. This earthquake apparently happened as the result of movement on the Swan Islands fault, which is a segment of the boundary between the North America and Caribbean plates. The plates there move about an inch a year and cause frequent earthquakes. The last major one caused by friction between the North America and Caribbean plates happened in February of 1976 in Guatemala. That one measured 7.5 on the Richter scale and resulted in almost 25,000 deaths.

Despite the magnitude and proximity, this earthquake appears to have done far less damage. As of May 29, the USGS reported six fatalities, 40 injuries, and 130 buildings damaged or destroyed in northern Honduras, with the earthquake also felt in the entire region.

I read about the earthquake a few hours after it had occurred and worried about how it had affected Roatan itself. The Cocoview resort has a website with two webcams as well as a very active bulletin board. I was relieved when I saw both cameras online, showing no apparent damage to the dock area with the boats nor to the structures on the water in front of the resort.

Apparently, Cocoview had neither lost power nor internet access for any length of time as reports began coming in on the CoCo Chat bulletin board. "Doc" Radaswki reported that everyone on the staff and their families were okay, and that the resort itself was okay as well, except for broken water pipes and major clutter from things falling down. He reported that the home of Jorge, who had been our boat captain the first time we visited Roatan, was badly damaged.

There were also reports from underwater and those sound quite intense. It was reported that the wreck of the Prince Albert had a big buckle and crack in one area, and another new crack running all the way down the ship from top to where it rests in the sand. It was also reported that huge pieces of coral had broken off walls and toppled.

A second report by the same source (user name Habib at CoCo Chat) said that a large number of sponges had simply been sheared off at the base, that there was much damage to Neuman's Wall near the Prince Albert, with pieces broken off the wall and falling to the bottom, exposing edges of long dead coral. It was mentioned again that the Prince Albert had developed large holes, with rust clouds still spewing out. Habib also reported "weird noise we are all hearing underwater...like distant sonic booms reminding me of rolling thunder...you can feel the concusions in the water..."

The underwater reports sound drastic, above water it seems that the area got away with far less damage than could have happened with such a strong earthquake so close. The 6.7 quake that hit Los Angeles in 1994 caused $20 billion in damage.

Doc Radawski reported a couple of days later that two popular dive sites -- Mary's Place and Calvin's Crack -- appear to have survived intact, with sponges sheared off and some new cracks visible on top of the reef, but no visible structural damage or changes.

Dr. Rob Davis of the Whale Shark & Oceanic Research Center on Utila also checked the south east and south west dive sites and found only "minor damage here and there." He reported that the "Labyrinth had a new crack, but overall nothing too dramatic."

Two other divers reported that the damage they saw was depressing, but that for those who don't know every nook and cranny of the sites, there is still a lot of beautiful reef left. They, too, reported that the big barrel sponges do seem to have suffered the worst damage, and that a chunk of Newman's wall closest to the wreck of the Prince Albert came down. They had also gone to the Anka's Place dive site and when they went over the edge of the wall, there was just two hundred feet or so of gray concrete-looking rubble instead of the coral wall and overhang. They also visited Calvin's Crack, and found that other than a couple of big sponges that had come off, the site looked much the same.

Posted by conradb212 at 03:39 PM | Comments (0)

May 20, 2009

Diving the Folsom Lake parking lot

For the first time in three years I got to dive again in Folsom Lake where I'd done my certification dives three years ago.

Folsom Lake is, strictly speaking, not a lake but a reservoir, with the water held back by Folsom Dam. The dam was built in the 1950s to provide flood control, electricity, and water for irrigation and drinking. When full, the lake covers an areas of about 18 square miles, not huge, but large enough to have marinas with many hundreds of boats. Folsom Lake, however, is rarely full. For one thing, its flood control duties mean that it must always hold some capacity in reserve. For another, it can get pretty dry in California, and so the amount of snow falling onto the Sierra Nevadas to the east of the lake will determine how full the lake will be in any given year.

The volume of reservoirs is commonly given in acre-feet, an acre being roughly 44,000 square feet (43,560, to be exact), an area just a bit smaller than a football field. An acre-foot is the volume that covers an acre with one foot of water, or 43,560 cubic feet. Folsom Lake's capacity is given as 975,000 acre-feet, which is about 318 billion gallons, or for those who think in terms of oil, about 7.5 billion barrels. As far as reservoirs go, Folsom Lake is not a giant one, being dwarfed by Shasta and Oroville that have capacities of 4.5 and 3.5 million acre-feet, respectively. Because of its relatively small size and reliance on snowfall in the Sierras, the waterlevel of Folsom Lake tends to go up and down dramatically. On May 20, 2009, with the lake almost full at 932,000 acre-feet, the water level elevation was 462 feet, but elevation can vary from a maximum of 480 feet to a minimum of about 350 feet, a difference of 130 feet.

I'd gone up to Folsom Lake during times of drought when the waterlevel had fallen to just 22% of capacity with large areas of formerly submerged land suddenly dry. The lake level had gone down so much by the end of 2008 that visitors were asked to stay away from what could be archaeologically valuable sites, such as the remnants of building foundations from farms and other structures that once stood where Folsom Lake is now.

Since the Folsom Dam was designed not only for flood control but also as a recreation area, its designers made sure that the lake would still be accessible for boats when the water level was low. For that purpose they built a secondary parking lot and boat ramp at the far end of the Brown's Ravine marina area. That parking lot is underwater when the lake level is high. When we did the certification dives, instructor Chuck had casually mentioned "the parking lot" but I had thought it was some sort of natural underwater formation, not a real parking lot. But when we went in, we were actually diving and hovering over the parking lot.

Below is an aerial view of the submerged parking lot. You can clearly see the outlines of the lot underwater at 10 o'clock off the dry land. On our dive, the water level was quite a bit higher yet.

This time, the water level was higher yet, with the access road to the parking lot itself flooded halfway up. A lot of trees were almost entirely underwater, so water this high is apparently not something the trees expect. Our plan was to enter the lake at the access road to the parking lot, then follow the perimeter of the parking lot counter clockwise until we reached the boat ramp and then go down the boat ramp if conditions were conducive.

We had no idea what the water temperature was going to be, or what visibility to expect. A web search yielded widely varying temperatures. A triathlon event that included swimming in the lake suggested water temperatures in the high 60s towards the end of May. However, for environmental reasons (fisheries, etc.), the operators of Folsom Dam are trying to release water at a steady 57 degrees. As for visibility, I had thought it might be quite good. After all, 70% of all the water in Folsom Lake was brand-new water directly from the snow-packed Sierras. So I had visions of hovering over the parking lot and being able to see it from one end to the other.

Reality is always a bit different. We had suited up in 7mm wetsuits, gloves and hoods, and that turned out to be a good choice. The water temperature on the surface and down to about 15 feet was a balmy 71 degrees. Though the water was very clean, visibility was only fair, perhaps 10-20 feet. We followed the yellow double line in the center of the road, then the right edge of the road until we reached the parking lot. Between 15 and 20 feet was a fairly steep thermocline with the water temperature dropping from 71 to 57 degrees. It still didn't feel cold, though. 23 minutes into the dive we reached the top of the boat ramp which was now 25 feet underwater. We went down the ramp along its rightside edge. It was getting colder now and there was much less light. At 75 feet we still had not reached the bottom of the ramp, but decided to turn around as the water was now 49 degrees. Amazingly, it felt nowhere near as cold as in San Diego at the Yukon where 50 degrees had felt debilitatingly cold.

Below is a picture of the lot when it is not flooded. The yellow "No Parking" block marks the top of the boat ramp that was about 25 feet underwater on our dive.

Going back up the ramp took another ten minutes and then we followed the perimeter of the parking lot on the other side of the ramp. The whole time we'd seen plenty of fish, mostly bass, and numerous schools of tiny fish. The bass did not seem afraid in the least and easily came within reaching distance. We also found a pair of fully functional reading glasses and what looked like a small, cut diamond (it wasn't real). I am not sure how Carol managed to find it, but she did. A good hour into the dive we left the perimeter of the parking lot and promptly got lost on it. Since we'd been in just 15 feet of water for a while, a quick ascent to the surface showed which direction to go. At the end it had been a 70 minute dive, and a thoroughly enjoyable one.

What surprised me was just how much silt and sediment had formed on the road and on the parking lot in just a few weeks. It wasn't enough for a serious silt-out, but swimming close to the bottom whirled up quite a bit.

A lot of people sneer at Folsom Lake for diving, even those who got certified there. For the most part, they are right. There isn't much to see underwater and during certification it's mostly descending to 30 feet or so and demonstrating skills. But diving the parking lot and the ramp was a lot of fun. It just felt so weird to dive over where we had parked just a couple of months ago. And during the drought last Fall, we even had taken the car down the ramp and parked on the lake bottom, probably a good deal lower than the 75 feet we had reached on the ramp.

With the conditions we encountered, not only is Folsom Lake an enjoyable dive, but it'd also make a terrific place for underwater navigation on the parking lot, and for deep dive training by simply following the ramp down (it probably ends well below 100 feet when the lake is this high). And the price of admission is a grand total of eight dollars for a day pass to the area.

The image below shows the computer log of the dive. Going down and then back up the boat ramp made for one of the more interesting looking dive profiles.

Posted by conradb212 at 04:59 AM | Comments (0)

May 02, 2009

Nasty letter from PADI

Today, much to my surprise, I received a nasty letter from PADI's legal department. It went:

"Dear Mr. Blickenstorfer:

I am with PADI's Legal Department. PADI is the distributor of DSAT’s Recreational Dive Planner. Please be aware that you do not have the rights nor permission to use DSAT's various dive tables on your site http://www.scubadiverinfo.com/2_divetables.html. To be able to use DSAT’s copyrighted materials, a license agreement would need to be in place. At this time, we have no interest in pursuing a license agreement.

We must request that you please take these portions of your site down immediately. Also, we would appreciate a written confirmation from you that you understand and will comply with this request. Thank you in advance for your anticipated prompt cooperation."

The missive was directed at my having a picture of the PADI dive table on our scubadiverinfo.com site. PADI dive tables are quite complex and convoluted, and so I took the time explaining them with examples. Everyone said that was a great idea. Everyone except PADI, that is. Don't these folks realize PADI, and diving, needs all the help it can get?

And not only are those puffy legal eagles threatening me, but then they condescendingly declare that "At this time, we have no interest in pursuing a license agreement."

Get real, guys!

Posted by conradb212 at 12:27 AM | Comments (0)

March 30, 2009

The importance of picking the right dive suit

When I first started diving, I didn't think much about water temperature. The pool where I did my training dives was comfortably warm, and I was far too occupied with figuring out how to breathe and move underwater to worry about being hot or cold. When we selected our rental gear at the dive shop for the certification dives in Folsom Lake, I picked whatever fit as opposed to checking the anticipated temperature of the lake and then getting the appropriate gear. And when I worked on our scuba website and wrote a section on exposure suits, the insulation guideline table from Carol's NAUI course materials meant little to me.

That table said to wear a dive skin in water 85 degrees and above, a thin wet suit for 75 to 85 degree water, a 5-7mm wetsuit for 55 to 75 degree water, and a dry suit for temperatures between 35 and 55. So when it came time for me to get my own wetsuit, I figured 7mm was best as it provided the widest range of protection.

The Telos 7mm suit I picked as my general purpose dive gear certainly did provide good protection, but I soon realized that there were drawbacks. The 7mm material is thick and bulky, making it difficult to pack the suit on trips. The suit was very difficult to put on and I was usually exhausted before I even got in the water, just from getting into the darn thing. And even a bit of sun or exertion on dry land led to overheating.

Still, I wore the 7mm suit on all my early dives, including the rivers and springs of Florida (71 to 73 degrees) and Lake Tahoe which was usually 66 or so on the surface and then ranged from a chilly 48 degrees at 110 feet to the mid to high 50s on most dives. Once I was in the water I felt just fine in Florida, and really wasn't too cold in Tahoe. Getting into and out of the suit, however, was a constant pain, and often what I remembered most. I thought working up a major sweat and being exhausted from putting on the wetsuit was the norm. I did buy a second 7mm suit, one that fit me better and was more stretchy. That made a substantial difference.

I bought a 3mm wetsuit for my August trip to Honduras where the water was usually 84 to 86 at the bottom. That was perfect and there probably wasn't even a need for a suit as the weather was hot and sunny. Putting on the 3mm suit was infinitely easier than the thicker suits. The 3mm suit also dried much quicker and took up much less space in my luggage. After those wonderful dives in tropical waters I thought I had it all figured out. 3mm worked in warm water, and as soon as it got a bit colder, or even quite cold, 7mm would do the trick.

Then I found out it wasn't that easy. When we returned to Honduras in December, the water was still 78 to 80 degrees at the bottom, and usually 80 to 82 at the surface. I thought that was plenty warm enough for wearing my 3mm suit, but I was usually cold. I also found that overcast skies and wind can make a huge difference. It's one thing to emerge from the water and into the warm sun, and quite another to come up to wind and rain. Wind, especially, can be brutal on an open dive boat, and somehow the difference between a sunny and a gray, overcast day is huge, too. I was so cold that I bought a diveskin to wear underneath the 3mm suit, but found that it hardly made a difference. I also bought a Shammyz jacket to keep warm on the boat.

The wreck diving trip to San Diego then showed me that even a 7mm suit with thick boots, thick gloves and a hood was not enough to keep me warm in 50 degree water, at least not when I was staying down in that cold water for 30 minutes at a time. It felt brutally cold, to the extent where I could not enjoy the dives and had to skip some. I felt that the gray, dreary sky contributed to feeling cold once I was back up. I tried diving with the skin under the 7mm suit, but it made little difference.

What I learned is that there's nothing like personal experience when it comes to picking the right suit to wear on your dives. There may be guidelines, but you need to experience how it feels to you and what your personal comfort level is. I really thought that a couple of suits would cover the whole range of water temperatures you're likely to encounter on typical dives, but, at least for me, that's not so. Knowing what I know now, I'd have bought a 5mm suit for my December trip to Honduras, and I am now contemplating dry suit certification so I'll be able to enjoy my next cold water dives.

Why not just tough it out? For some that my be a solution, but I don't think it's worth it. Dive vacations and dive trips are expensive, and not being able to enjoy dives, or even having to skip dives, because of being cold makes no sense at all. As far as I am concerned, it can even be dangerous if you find yourself shivering underwater instead of paying attention.

I should also mention that the type of wetsuit you wear makes a BIG difference on your buoyancy. That's another thing I only learned through experience. I thought there couldn't possibly be much difference between a 3mm and a 7mm suit, but there is, and you have to compensate by adding or subtracting weight from your weight belt or your BC's weight pockets. Even gloves and a hood can make a difference.

Posted by conradb212 at 03:16 PM | Comments (0)

March 24, 2009

Wreck diving off San Diego, California

Diving the Yukon

No, not the Yukon up north but the HMCS Yukon, a Canadian McKenzie Class destroyer that now sits in 105 feet of frigid water a couple of miles off the coast of San Diego. As far as wrecks go, the Yukon is a big and imposing one. It’s 366 feet long, displaces almost 3,000 tons, and has some menacing looking guns. The ship was launched in 1961 and sunk in July of 2000 to form an artificial reef. Unlike ships that sink all by themselves, the Yukon was helped along, after having been thoroughly prepped for scuba diving adventures by cutting a large number of holes into its sides and decks. The actual sinking of the Yukon was supposed to be an orderly event witnessed by thousands of boats. Maps had been drawn, cutouts were all neatly marked, and there were even laminated “You Are Here” orientation maps in many strategic points inside the vessel. (see article "Map the Yukon" in Geospatial Solutions)

The Yukon, however, had other plans. Rougher than anticipated seas made the ship take on water through the cut-outs in its side, and so she simply sank, ahead of time. She also did not neatly settle on the sandy bottom, but rolled over and came to rest sideways. Some of the planned cutouts remained unmade as the shape charges never went off, and the nice, neat map, while still technically accurate (except for the cutouts), isn’t of much use with the ship now laying on its side. Those who want to see how the Yukon rests at a depth of 105 feet should get Franko’s HMCS Yukon Deck Plan. It shows an exploded view of all six decks as well as floor plans and all the current cutouts.

I had been invited to dive the Yukon early on in my scuba career, but at that time I had not been ready yet. Now I felt I was, and so I had signed up for three days of wreck diving with our friends at Fisheye Scuba. We drove the 500 miles or so from Folsom to San Diego’s Mission Bay area and stayed at the Dana Hotel that was right across the street from our dive charter, Waterhorse. The Dana Hotel is also very close to SeaWorld San Diego, but, in all fairness, why go to an expensive seaworld theme park when a mile away you can see and experience the real thing?

About 16 people had signed up for the trip, some doing their PADI wreck diving certification dives and others, like us, just doing the diving itself. I had no idea what to expect. This was going to be my first time in the waters of the Pacific. Kate of Fisheye Scuba had said the water temperature was going to be in the high 50s on the surface and 52 or so at the bottom. Half the divers were going to wear drysuits and the others wetsuits. Not having a drysuit, I brought along my 7mm Scubapro Form wetsuit. And hood, and gloves. And not one but two pairs of Shammyz to keep warm, one of them with the special windbreaker that zippers on the outside.

Set the alarm for 6am and made it to the dock by 7:30am where there were already a number of folks unloading trucks, donning gear, signing papers and using a big dolly to get tanks and gear to the dive boat. Half an hour or so we were all on the boat, which was a cozy affair with a head, a nice cabin where the captain had set up snacks, fruit and beverages, and even a hot shower. The boat had its own compressor so they didn't even have to take the tanks off the boat to fill them. Carol had brought her two Nitrox steel-80 tanks (US$12 per fill as they had to take those off the boat); I used the rental aluminum 80s that came with the trip.

The weather was typical San Diego, that is all foggy so that it looked like it was a gray, overcast day. It’s just fog, of course, but it feels coldish and dreary anyway. The fog usually burns off around 11am or so, but not always, and sometimes it goes away and then comes back. Kate gathered her wreck class group for a briefing, and then the captain did a dive briefing of his own. The first dive was the big one, the Yukon. She’s a big one, we learned, just look at the bow and stern buoys (they were far apart for sure). Viz isn’t very good, like 20 feet or so. Look out for the surge as it can suck you right into an opening and spit you back out. Other than that, go down the line, do the dive, and come back up. It’s actually refreshing that it’s all so straightforward in something so potentially dangerous.

After having checked all my stuff and gear at least five times, including the Canon G10 in its underwater housing, the Scubapro dive knife I had strapped onto my right arm, and the little dive light, I did a giant stride into the darkish sea. You always heat up quite a bit in a 7mm wetsuit, and so the 56 degree water actually felt quite refreshing. Carol and I had vowed to stay close together and so I waited for her before I descended. Turns out she didn’t have enough weight and had to add another two pounds. I had guessed 24 pounds for me, and that ended up being just right.

Going down, the water was all green. I had a bit of a sinus pressure ache in my forehead at around 15 feet. So I stopped rather than force it and end up with a big nosebleed as I had in Honduras. The ache subsided and I resumed the descent. It quickly got colder and darker, and two minutes later giant shapes came into view, the Yukon. If you are not a diver you may think it must be quite interesting to simply float and look down onto a sunken ship. It is very interesting, but ship wrecks hardly ever sit in crystal clear water so you can really see them. Instead, they may be so broken that you hardly recognize them. It’s amazing what the sea can do to a ship in just a few years. Or it is so dark and murky that you can only see what’s practically in front of your nose. Now imagine a 366 foot vessel lying on its side, and you’re looking at it essentially in the dark and with a visibility of no more than 15 feet or so.

What that means is that things come into view and then disappear again. You don’t quite know what they are or where you are. I had thought the map would help me orient myself, but it was much too dark and murky for that. I was so enthralled with the adventure of it all that I actually completely forgot that the ship was sideways. All I could concentrate on was the encroaching cold, checking my gauges to make sure I didn’t get too deep or run out of bottom time, and, most importantly, not to lose Carol. We both had cameras and I was determined to at least take a few shots.

I was stunned at how much aquatic life had already taken hold on the ship. Anyone expecting a gleaming high-tech destroyer to still look pretty much the same after nine years underwater, not so. There’s a thick crust of coral, anemones and other sealife, with thousands of large and totally white anemones giving the ship a surreal look. Some kelp was floating around, too, showing just how strong the surge was. I tried to take pictures, but between the unfamiliar layout of the button controls of a new camera and the eerie surroundings, I didn’t get much. When the flash did go off, I saw that the coral surrounding the anemones was bright red.

Every dive is different. Even though the surroundings were quite intimidating, I felt calm and free of anxiety. I seemed to spend equal time taking in whatever sight I could of the massive wreck, making sure I did not lose my buddy, trying to take pictures, and checking depth and air. I did not come close to penetrating the wreck, or even come close to one of the openings. I really wanted to see the big guns but there was no time to do any exploring. While the wreck laid in semi-darkness where the lights came in handy, I could see light above and quite a few fish, whole schools. There wasn’t, though, anywhere near the variety I saw in Honduras. I looked at the dark shapes of encrusted metal and felt that anyone who got lost in there would hardly have a chance to come out alive or be found and rescued in time.

Time went very quickly. It was a bit hard to clearly see the data on my Uwatec Smart-Z wrist-mounted dive computer in the near darkness and so I made extra-sure to stay on top of remaining air. After 25 minutes at the wreck, at depths between 65 and 82 feet and at a constant temperature of 51 degrees, I was down to 850 psi and 6 minutes of nitrogen time. Though we had not moved around much, I had no idea where the descent line was and motioned to Carol that it was time for me to go up. Carol did know (it was only a few feet away) and we went up, doing a four minute safety stop at 15 feet. Using less air and being on Nitrox, she still had a good third left, and nitrogen time had never been an issue.

Back up on the boat I felt both elated and quite cold. Even a bowl of steaming hot minestrone soup didn’t eliminate all the shivering and so, after two test divers reported poor visibility at the second dive site (the cutter Ruby E), I decided to call it a day. I had dived the Yukon, and that felt really good.

No two wrecks are the same, and every wreck dive is different. Temperature and visibility can make a huge difference. A wreck in good light and clear water is totally different from a wreck in the semi-dark at almost no visibility. I am glad I did this dive. I enjoyed myself and I did not feel anxious. I did well. But I realized once again that this is not a harmless sport. The margin for error is very little.

Diving the Ruby E

After the very cold, murky dive to the Yukon I wondered what Day Two of our wreck diving trip would bring. I’d been asking myself why the dive boats go out early in the morning when just about every day in San Diego seems gray and foggy until about the time the dive boats return. I’ve heard a number of explanations, from the sea being calmer in the morning, to dive boat captains wanting to go home early, to the tide and such. I still don’t know what the actual reason is. It’s definitely no fun to get up early for a few hours of dreary fog when one knows the weather will most likely clear up around 11AM or so.

Anyway, I really didn’t feel too hot as we made our way across the street to the dock. Everything was damp and clammy and I racked my brain trying to figure out the best way to stay reasonably warm and dry through the process. At 8:15AM we took off onto the grayish sea under a grayish sky. First stop was a lobster trap rescue operation. Seems one of those crude, yet effective lobster trap cages made of chicken wire and rebar had gotten stuck. Ryan of Fisheye Scuba dove into the frigid waters. After a few minutes he re-emerged, mission accomplished. The captain of the tiny fishing boat was happy.

On we went to our first destination, which was the wreck of the 165-foot Coast Guard Cutter Ruby E originally designed to enforce prohibition and launched in 1934. The vessel then had a checkered history (including submarine control, fishing, salvage and even a bit of drug smuggling, and she ran under various names. The Ruby E is a much smaller ship than the massive Yukon and had been sitting on the bottom since her sinking in 1989, 11 years longer than the Yukon.

We geared up, with Carol donning the Liquid Image camera mask. The camera mask was invented by a camera located in the Sacramento area and combines a 5-megapixel CMOS camera that can also do video with a regular dive mask. This sounds somewhat gimmicky, and looks it, too, but the thing seemed well designed and we’d actually had had dinner with Liquid Image executives a few days prior to the trip. They’d explained the device, how it came about, and what it could do. We had offered to take it along for an underwater test. And while this version of the camera mask only had a 33-foot depth rating, we planned to take it down to the Ruby E, which sits in about 85 feet of water.

The water was green as we went down the descent line and it got dark quickly. By the time we reached the sandy bottom we could barely see the bow of the cutter. It was cold, barely 50 degrees, the visibility was poor (perhaps 15 feet), and there was a strong surge back and forth. Without being able to see much, exploring a wreck becomes a matter of slowly examining what appears in front of your eyes. The Ruby E was reasonably intact, but all surfaces were totally overgrown with a dense cover of small strawberry anemones and similar critters. There were none of the giant white anemones here as we'd found on the Yukon. We saw a good number of starfish that come in a wide variety of shapes, sizes and colors. Carol, aware that the camera mask was recording, kept moving so that her exhaust bubbles did not obscure the recording and also made an effort to keep her head still, which with the data mask meant the same as holding the camera steady. The mask apparently worked as it wasn’t fogged up and she did not seem to experience any problems.

I tried to get some good shots with my Canon G10, but it was mostly a futile effort. Between the surge and the cold, things just weren’t very pleasant. If a bit of cold and dark does not seem like a big deal, consider that this is a cold one cannot escape from. Down there, you cannot duck into a doorway to get reprieve from an icy blast or wind. You also cannot button your coat or pull up the zipper or a hood. What you’re wearing is all you got, and it cannot be changed. The dark and surge makes it worse. Add to that an unfamiliar place that remains largely hidden from sight, and things can get somewhat stressful in a hurry. I never felt truly anxious, but also did not enjoy myself. It was just too cold. Eventually it got so that I began to shiver. It was time to get back up anyway and, as usual, Carol almost instantly found the descent line (how does she do that?). At the 15-foot stop the water was back to 57 and, comparatively, felt like bath water. I was glad.

Back on the boat I wasn’t sure if I’d be able to do a second dive. Even sitting inside the cabin I was shivering, and even hot soup and a big cup of hot chocolate did little to warm me up. I felt annoyed by that as I am not usually that susceptible to cold. I really did not want to miss another dive, and so I willed myself to stop shivering and get ready to brace the cold water again.

In the meantime, Kate’s wreck diving students compared notes and had a critique, though I am not sure how much people actually heard over the noise of the engines. I don’t think much wreck penetration was done, but they got to practice site surveys, handling their reels, and other wreck diving techniques.

Diving kelp

The second dive was in a kelp field. I had read a lot about the kelp forest off the coast of California and didn’t quite know what to make of it. It sounded quite intimidating and invoked unpleasant memories of fighting off sea weed and assorted algae when I was a child. Whatever I’d read of the underwater kelp forests was invariably positive, though I’d also come across references of people getting caught in kelp and having to use knifes or requiring assistance to extricate themselves. Kelp, apparently, was also where a lot of fish and other critters hung out, and there were many accounts of divers suddenly finding themselves with a big fish or a sea otter or some other creature.

When we arrived at our destination, it really didn’t look very pleasant. A lot of what I used to consider "sea weed" was bobbing on the surface, making the water look murky and somehow not clear or clean. In his briefing, the captain described a ledge and rocky area underneath us and said we might expect to see some larger animals. He said stay below the surface to keep from getting entangled in the kelp once we came back up, and, should we get stuck, to simply drop down rather than fight the kelp. I didn’t quite know what to make of that, but in I went.

The water wasn’t much clearer here, but at least we didn’t descend into darkish depths. Instead, as soon as I dropped below the surface I saw the kelp forest, which turned out to be a magical world of gently swaying leafy plants vertically in the water. Far from being mere “sea weed,” kelp is intricate, beautiful, and unlike anything that grows on dry land. It isn’t just a stalk and leaves ether; instead, the plant makes a multitude of different tendrils, spirally growths, leaf-like structures held up by battalions of bulb-like floaters, and it all sways together in a gentle concert of fluid motion. It is captivating and Carol took numerous pictures.

We quickly reached bottom that looked much like the coral reefs of the Caribbean, only without the variety of fish and colors, or the clarity of the water. Instead, there was strong surge back and forth. Examining the bottom we found a lot of urchins and many starfish, a Garibaldi or two, and some other critters. I had read a book on urchin fishing in California, which had been a lucrative trade and industry in the 1980s and 90s when the Japanese bought up whatever enterprising professional divers could bring up. I somehow thought the urchins were just sitting on the ocean floor, but the vast majority is actually burrowed into the surface in roundish cubbies. I don’t know if they ever come out or simply stay there. Some are quite large, much bigger than I thought they get. Some seemed the size of basketballs.

We swam between rock outcroppings that rose to within 25 feet of the surface, then dropped down vertically to lower ground in the mid to high 40s. The water was colder and less clear on this side, but it was still fascinating to swim between the kelp plants. They were not dense enough to get lost in them or having to fight one’s way through by any means. There was plenty of room. I was getting cold again and began my ascent after 35 minutes or so. I’d found the boat’s anchor line and so had a clear shot straight up. Carol followed, taking many beautiful close-up and macro pictures of the kelp plants and some of the amazingly colorful critters that live on and between it. Some look downright psychedelic and when you look at the pictures later, it's hard to believe that something that beautiful is in the cold and dark water.

Me, I was glad I’d overcome the cold and made the dive.

Another dive to the Yukon

Our last day started like the first two, with a gray sky and a chill in the air. In addition to getting ready for diving, we also had to pack up our stuff, put it in the car, and check out. Logistics can get a bit overwhelming at times.

This time I decided to wear my Akona dive skin underneath the 7mm wetsuit and see if that helped me fend off the penetrating cold. The wetsuit certainly goes on easier when you wear a dive skin, but when you have to go to the bathroom, it’s yet another item to somehow get out of the way.

The first dive was a second descent to the Yukon. That was certainly alright with me, but I wondered whether a repeat dive was due to the wreck diving class or whether there were no other suitable wrecks. This was, after all, “wreck alley.” On this dive we were going to be testing the Liquid Image Camera Mask again, recording and documenting the entire dive. The water was 57 on the surface, but quickly got colder as we descended down the line into semi-darkness. This time our mooring line got us to the center of the Yukon. The world was all green down there and once again, it was difficult to make out anything but darkish shapes at the very edge of the 15-foot or so visibility range we now found ourselves in. They were parts of the ship, but it was mostly impossible to figure out which parts.

The top of the ship had a lush growth of kelp or weeds on it, and they were moving with the surge that washed over the ship. I descended down what must have been the deck surface in front of the bridge and found the water to be both calmer and darker. I was at 91 feet in 51-degree water; trying to get my bearings, trying not to get lost, staying calm, and figuring out where I was. Since it was so dark and murky, everyone stayed reasonably close together and so I was watching dive lights of my fellow divers as they shone into some of the cutouts, tied off lines, handled reels, and slowly entered the wreck.

Though I was very careful I temporarily lost sight of Carol, white fins and all, and felt a sense of frustration over that as I wanted to experience and explore for the precious minutes down on the wreck rather than spend the time searching for my dive buddy. At this depth and under these conditions I really didn’t want to dive solo, and I also didn’t just want to join another group. Fortunately, Carol found me after a few minutes.

My total time down by the Yukon was 22 minutes, from the time I arrived at the bottom of the descent line to the time Carol and I began our ascent. It didn’t feel that long, but it also wasn’t long enough to do, or even start, anything meaningful. So the dive was mostly looking at this and that, and simply holding it together at this murky depth. I took some pictures of the white anemone, marveled at just how colorful the growth was. The ever-present strawberry anemone, whose scientific name is corynactis californica, covered large areas of the wreck, bursting in bright red whenever touched by a flashlight or dive light. These are really neither anemones nor coral, but somewhere in between. Individual strawberry anemone don’t grow larger than an inch, but they can cover something as large as the wreck of a destroyer.

Again, I cannot overemphasize the difference between 90 feet in warm, clear, bright Caribbean waters and 90 feet at 50 degrees, poor visibility and near dark. It’s a bit like the difference between cruising along in sunny daylight, enjoying yourself, and driving at night and in the rain or snow and having to really concentrate on what you’re doing.

The ascent means a progressively lighter shade of green, and also noticeably warmer water. Warmer, of course, is relative as it is only the difference between 51 and 57 degrees. I swam to the dive boat, took off my fins, climbed up onto the deck and plopped down, exhausted, but happy. It’d been a good dive, and it felt like a monumental thing.

Carol thought the camera mask had given up its ghost as it looked like the lens had condensation or water inside. Later I found that the mask had recorded the entire 40-minute dive in one giant 2GB file.

After the dive I was unable to warm up and couldn’t stop shivering no matter what I tried. So I decided to skip the second dive, another kelp dive, and watch the goings-on on the dive, the San Diego coast, and the bubbles of my fellow divers. The bubbles hardly moved. When you’re down there you think you’re moving around quite a bit, but the bubbles tell otherwise, at least when there is no current to carry you away.

Posted by conradb212 at 10:05 PM | Comments (0)

Getting started with dry suits

After shivering through four 50-degree water dives in my 7mm wetsuit, I seriously began contemplating a dry suit. On the dive boat I’d been watching the divers in our group who wore dry suits smiling and being comfortable whereas the wetsuit contingent was grimacing and trying to warm up with steaming cups of hot chocolate or bowls of minestrone soup. I’d missed two dives because I simply had been too cold. Dry suits are expensive, but so is missing dives on expensive dive trips. My missed trips probably would have made a nice down-payment on a dry suit.

What are dry suits? They are the kinds of protection divers wear in cold water, 50 degrees and below (and as far as I am concerned, make that 60 and below). As the name implies, a dry suit stays dry inside and allows no water in, and that is its primary purpose. The staying warm part comes from wearing undergarments that trap an insulating layer of air. Dry suits are made of high tech components and materials, essentially technology that emanated from the space program, with some bicycle tire technology thrown in. Using a dry suit is significantly more complicated than a wet suit, and there are things that can go wrong. This is why there are special classes for dry suit diving and certification. And expect to pay quite a bit more for a dry suit than a wet suit.

Unlike wet suits that come in various configurations, almost all dry suits are full body suits, including integrated boots. They are totally sealed, and have special waterproof zippers. The seals around your wrists and neck are made of latex or neoprene, with large contact areas to provide the best possible seal. Latex seals are thinner and seal better, but they are easier to rip and some people are allergic to latex. Neoprene seals wear better, but are thicker and need to be stretched to fit. Seals are usually the first thing to break on a dry suit. They can be replaced, and some dry suits even have seals that can be zipped on and thus replaced.

As stated, the insulation provided by a dry suit comes from the air inside the dry suit. Air is a much better insulator than water, but unlike the water layer inside a wetsuit, the air inside a dry suit compresses and expands, which means the dry suit needs an air valve that allows for inflation from a low-pressure supply from the air tank. The valve is usually located on the chest. That way, the divers can add more air as they descend. There is also an exhaust valve, or “dump” valve to purge expanding air during ascent. Controlling the air inside a dry suit requires training and experience. You don’t want for all that buoyant air inside your dry suit to end up in your legs and you ascending feet first.

Dry suits can be made of a variety of different materials. Generally, they are foam neoprene, compressed and crushed foam , or membrane coated materials. Foam neoprene is the same kind of material that’s used in wet suits, which means dry suits made of it provide a bit of insulation in addition to that provided by the air layer, but their buoyancy varies with depth. Compressed and crushed neoprene dry suits use special kinds of neoprene material that has been specially prepared to strengthen the material, bonding and stitching. Membrane, or “shell,” dry suits use a waterproof coating over the fabric. The coating is usually urethane or a laminate of rubber and some tough synthetic material. They are lighter and more flexible than neoprene suits, but provide almost no insulation by themselves and have no positive buoyancy. The materials used do not stretch and are generally more loose-fitting, which makes it easier for air to move around and potentially get trapped where it shouldn't be.

It so happened that Carol had a dry suit whose arms and legs had always been too long for her, and so she suggested I try that on. I put on the thick, full-body thermal underwear first. The membrane suit itself had its waterproof zipper across the chest. I stepped into it and got my feet into the integrated boots. I then made my left hand as small as possible and squeezed it through its seal, using the fingers of my right hand to carefully stretch the seal. Same for the right hand. Then I gently used the fingers of both of my hands to grab and evenly stretch out the head seal so I could get my head through the latex seal. Carol then carefully closed the waterproof chest seal. I was now wearing a dry suit.

I had always wondered how the watertight seals worked and whether they’d feel uncomfortable and constricting around the neck. The initial answer was, “some,” but actually almost less than the neck cutout of a thick 7mm wetsuit.

I was now sealed inside the dry suit, together with a good bunch of air. Carol showed me how to hug myself with one arm, use the hand of the other to reach inside the neck seal and provide a path for air to escape, then kneel down to push out most of the air. Remove the hand so that the airtight seal re-forms, get up, and tighten the sash around your waste.

I looked in the mirror and what I saw was very different from the sleek, form-fitting look of a neoprene wetsuit. Instead, the dry suit wrinkles and crinkles and doesn’t look very elegant at all. This one had another interesting touch in that it was half black and half hot, screaming pink.

So now it was time to see how the suit worked in the water, and for that I used the pool. I got in up to my thighs and instantly felt the weight of the water compact the suit around my feet and legs. There were very small bubbles emanating from the left knee and some from the right, which Carol felt was probably air trapped underneath an outer double layer of material. I then stepped fully into the shallow end and, for the first time, experienced the weird “grab” of a dry suit as you enter water. The suit tightens around you in a weird way. Imagine one of those vacuum freezer bags where you use a machine to suck the air out of the bag so it fits tightly around the meat to be frozen. It’s an interesting and not unpleasant feeling.

I donned my fins, a dry suit hood, gloves and my mask and snorkel and began snorkeling around the pool, which was at about 58 degrees. I felt warm and, of course, dry. Water still got into my gloves, of course, but the dry suit hood almost made it feel like my head was fully protected as well. Despite having let out more air through the neck seal, I was hugely positively buoyant and couldn’t even get down to the bottom of the pool to retrieve the thermometer that had rolled down to the deepest point.

I played around for perhaps half an hour, getting used to the feeling, then got out. I still felt warm and cozy, though by now my feet were a bit cold and I wondered if my butt had gotten wet. I opened the suit and we began testing everything for dryness. All dry, including butt, but my left sock was definitely wet, and the right one a bit as well. The bottom of the thermal underwear, however, was dry, right down to the ankles. So there’s a bit of leakage in the boot region somewhere.

That was that for the day. I’d finally had my first taste of how a dry suit feels. Next we’ll hook up an inflator hose to the chest valve and try the suit with the BC and a tank.

Posted by conradb212 at 05:29 AM | Comments (0)

February 23, 2009

Getting the real scoop on new dive locations

It's interesting how almost three years after I got my Open Water Scuba certification I still find things they simply don't tell you in class, like what diving in certain places is really like. For example, Cozumel, a smallish island off the east coast of Mexico, is a very popular place to go diving and it's high on the list of places I want to go this year. So naturally I want to find out as much as I can about diving in Cozumel.

If I try Google I find endless commercial links. As of this writing, February 2009, while Google is certainly a phenomenal search engine, it has also become so commercial that it's hard to sift for the nuggets of real information in a giant flood of commercial links. Google is starting to look more and more like the old Yellow Pages. Sure, I can probably link to every dive operator's website from Google, and also to all the travel agencies and hotels. But that's not the information I am looking for.

I want to know what it's like to dive in Cozumel. Like, where on the island do people dive? Are the dive spots all in one place and if you don't live close your boat rides will be much longer? And when you book a Cozumel dive package, does the hotel also have its own dive operation, or are they contracting it out to third parties? And if so, to whom? If there are resorts with their own dive operations, is it better to go to one of them? What's it like to deal with a third party operation? Does that mean they pick you up at the hotel? Or do you have to walk/drive to some pickup point? If you deal with a third party, is there a pecking order? Are there outfits to stay away from? What if you want Nitrox? Will my hotel's operator have it? If not, what do I do?

As far as hotels go, as expected, there seem to be significant differences in pricing. In part, that's because some include all meals whereas others do not, and some are big, luxurious places with lots of facilities whereas others are not. So if all I want to do is go diving every day, does it still make sense to stay at a fancy resort that advertises all sorts of luxury amenities included in the price when in all likelihood I won't ever use them? Would it be better to stay at a place that specializes on divers, or one where you simply get a decent room and good access to the pier?

Is the location of the hotel important? Some advertise they are close to downtown, or just a short cab ride away. Does that really matter? Would it actually be better to be farther away from a town or village? Or does being far away mean you're stranded with nothing to do and nowhere to go?

What's the weather like for diving and how warm can I expect the water to be? That's pretty important when figuring out what wetsuit and clothing to bring along. And will there be bugs/pests that are worse in some seasons than in others? Which ones?

Then there's the diving itself. Apparently, a lot of diving in Cozumel is drift diving, which means the current is strong enough so you can't just go on a dive and then return to the dive boat. Instead, you go down, let the current carry you along and then resurface at some other point. The dive boat follows your bubbles and will pick you up when you surface. This presumably means that groups need to stay together and go up together. Which I suppose also means that whoever runs low on air first will dictate how long a dive will be, as opposed to non-drift places where you can always stay down longer if you still have enough air. I've heard people complain about very short dives on Cozumel, like mostly in the 30 minute range. I don't know if this is true, how dive masters in Cozumel handle dives and divers, and just exactly how this surfacing together works.

I read that there are "large" boats and "fast" boats. Apparently, "large" one are just that. They can carry a couple dozen divers or more and have some amenities. "Fast" boats appear to be much smaller, with just enough room for six divers or so. So who decides what boat to take, who gets on a boat, who will dive together, and where the boats will go? If I go with a group, will the group be split up and never dive together?

Not knowing any of this drives me nuts. I like to know what to expect so I can make an informed decision. I know I can just sign up for one of the trips at a local dive shop and they arrange everything for me and all I have to do is show up. That's probably how most people do it. But why is it that it's so damn hard to get the real scoop on a place, the real information? I often use Wikipedia as a last resort for commercial-free factual information. There's a brief Wiki entry on Cozumel, but apart from saying "scuba diving is still one of Cozumel's primary attractions" there isn't much useful information there either.

It's really interesting that at a time where we have access to instant, endless information, it still all comes down to trial and error. Unless I go to Cozumel to find the answer to all my questions firsthand and on location, I just won't know. And maybe that's not such a bad thing.

Posted by conradb212 at 03:21 PM | Comments (0)

December 21, 2008

Return to Paradise

Flying back to Roatan felt like going back to paradise, but this time I knew what was coming, I knew the routine and knew what to expect. Another great week of exploring underwater at what must be one of the best dive resorts in the world.

It was colder this time and occasionally there were rain clouds, gusts of wind, and the puddles of the rainy season. If that sounds like a bad thing, it wasn't. It was a wonderful week of diving at CoCo View resort that I wouldn’t want to miss for anything. The newness of the first trip there was replaced by the sheer joy of being back to a magical place and looking forward to all the things I knew I'd experience and enjoy. And discovering new things I'd missed the first time around. In a way it was like the difference between a first date and a great relationship. My initial romance with Roatan now seems destined to becoming a long-term relationship.

This time we stayed with our friends Bob and Diane from Tennessee. They’d been to CoCo View numerous times, qualifying them as “CoCo Nuts,” and they had rented one of the beach houses at Playa Miguel, the peninsula between the man-made canal and the beach. It was a nice place with generously sized showers, good water pressure and plenty of hot water (which is a very good thing on a dive trip). There were trail bikes to get back and forth between the resort and the beach houses and it all worked very well.

It was great to see familiar faces in the office, dive shop, dock and boats. I had looked forward to having Eddie and Jorge again, our boat crew from the summer, but this time we were assigned to the CoCo View II boat with divemaster Jessie and captain Ruben. They turned out to be great guys as well. Jessie is an easy-going, experienced divemaster who had also worked on an Aggressor liveaboard and is a master at finding and pointing out critters. And Ruben sure knows how steer the big boat through rough water.

I had wondered what the water temperature was going to be like in December. In August we’d had a balmy, tropical 86 degrees. In December it was more like 78 to 80 degrees, still warm but a definite difference, especially with the wind blowing when you got out of the water. The resort was full, too, with eating sections in the Clubhouse extending into the play and upstairs areas. The dive boats were full, too, with ours having 19 people assigned. A full house also meant that the lists for extracurricular and optional activities were quickly filling up. The shark and dolphin dives were all booked by Monday morning and so that decision was made for me. No sharks. Next time.

As returning guests we attended the orientation Sunday morning but skipped the orientation dive where those new to the resort were being shown the ropes. Instead, we went right to our first boat dive. In August I’d been a nervous wreck before that first ocean dive. This time I was completely calm and couldn't wait to get into the water. The first dive site on Sunday was Valley of the Kings, where the drop-off on top of the coral reef is around 30-35 feet and then there’s this gorgeous sloping, valley-like cut in the reef instead of just going over the edge of the wall. We'd done that site before, but last time I had stayed shallow as I'd been experiencing those nose bleeds and didn’t want to push it. This time I found myself completely comfortable and actually went down to 92 feet. Some sites lend themselves to deeper dives better than others. Visibility plays a factor, but also the terrain. Here, the viz was very good and the sloping valley made going a bit deeper easy and unintimidating.

I also decided to use air instead of Nitrox. I think I was actually the only one on our boat who used air. I’d felt fine on Nitrox in August, but Nitrox cost eight dollars extra per tank while air was included. If you used Nitrox all week it cost US$125. I figured I’d do an average of three dives a day for a total of 18 dives, so I’d have paid about seven dollars extra per tank, still expensive. For those doing four dives or more a day it made perfect sense. Anyway, I did not want to feel like I needed Nitrox to dive or enjoy diving.

Was using air instead of Nitrox any different? Not in the way I felt. In fact, I felt exactly the same. I was warned that I’d feel tired and exhausted after a few days diving on air, but that did not happen. There is one difference, though. With air you do have to watch your dive computer more frequently so as to not break the limits of no-decompression diving. Every time I went deep (80-100 feet), the remaining nitrogen time quickly dropped. It also dropped if I descended again by just a few feet after I’d gradually come up to shallower depths.

My second dive this time was a drop-off at Newman’s Wall. We went down to about 75 feet and began ascending when my computer showed eight minutes of remaining nitrogen time at that depth. Once we reached 30 feet about 35 minutes into the dive, nitrogen time was back up to 99 minutes, or unlimited. However, we then returned to the resort via the Prince Albert wreck and that got me back down to about 50 feet. Nitrogen time quickly dropped to just one minute and then I ran out and into my first-ever deco stop situation. The computer only wanted a minute at ten feet and the deco warning quickly disappeared as I slowly ascended, but it was a first for me and from then on I watched my dive computer even more carefully.

On my subsequent dives I found that my remaining nitrogen time was always considerably less than Carol’s, who was using Nitrox. I also found that diving deep (I had two dives deeper than 100 feet) was okay as far as nitrogen time goes as long as I then didn’t do another dip of more than 15 feet or so.

In all my dives, it was the recommended time limits of about 60 minutes per dive and my air consumption that determined the length of my dives, and not the fact that I used air. As far as air consumption goes, I fully expected to use a lot less this time around than back in August. Somehow that didn’t happen. Though I couldn’t have been calmer and more relaxed through most of my 16 dives, on some I actually used more. Go figure.

I got a chance to learn a bit more about how depth affects me. I am still convinced that psychology plays a big part. If you think something is going to happen or change at a certain depth, then likely it will. In his book "Deep Diving," author and deep diver Brett Gilliam mentions a study where symptoms developed pretty much based on what a group of divers was told would happen. Me, I did feel a little twinge of something every time I passed 100 feet. The air tasted different and I felt different. I also noticed that by and large, 80 feet seems to be the depth where I start feeling a little different. It’s an entirely good feeling. The air tastes slightly more metallic, I feel very calm and appreciative of diving. I found that I love to cruise at around 80 feet.

Doing the same dives again can be greatly rewarding. I was thrilled to get to go back to Calvin’s Crack and Mary’s Place, the two dives where you get to go through deep, narrow canyons. This time I took more time to look around and enjoy the wonderful scenery inside the crevices. Carol, who was filming high definition video with the Bonica underwater vidcam we tested, went through Mary’s Place first so that she’d have undisturbed visibility. I was behind her and stayed a good distance back. Yet, even though divemaster Jessie had asked people to keep their distance and was waving in two at a time, when I turned around I still had a diver practically on top of me and three more backed up right behind me. What’s the rush?

On Wednesday we did a day trip to the other side of the island by boat. I wasn’t feeling great as the relentless wind and perhaps some infection had conspired to make my head feel stopped up and I felt pretty miserable. We almost didn’t go, but I wasn't going to skip precious dives unless it was absolutely necessary. I felt better on the boat and we ended up having three terrific dives. Two of them were drift dives where the boat dropped us off and then picked us up a ways down-current. I saw sea turtles for the first time and a whole different underwater scenery than on the southside of Roatan. Instead of flat reefs and then walls, the northside has lots of fairly flat sandy areas and then spectacular sloping reefs.

Captain Ruben docked the boat at Half Moon Bay and we had a picnic on the boat. Then there was an hour or so of free time to explore West End. This was quite an experience. The main drag was unpaved and essentially one pothole next to the other. There were colorful little shops and boutiques and even PADI “5-star” diveshops, all in modest clapboard huts. It was probably more primitive than what I remember from vacations in Spain and France in the late 1950s. We bought a couple of little knicknacks though Carol was taken aback when Christmas ornaments she liked carried the dreaded “Made in China” sticker. She told the crest-fallen salesgirl we wanted things made on the island and hadn’t come all this way to buy stuff made in China.

The boat ride back was rough. The beer coolers were open now and there was Rum and Tequila, and so the drinking contingent of our boat, which was most, had a grand time and seemed wholly unaffected by the boat’s tossing and pitching. And a pit stop halfway home served to relieve accumulated pressures. We were unaffected, too, but there were times when I wasn’t sure how much more the boat could take. I was happy to find that apparently I don’t succumb to seasick easily, though I won’t be taking that for granted.

On the last day of diving we got to see the wreck of Mr. Bud, a fishing and cargo ship resting on a sand bank at the edge of a wall at 50 to 65 feet of water. Visibility was excellent and I actually got to take in the whole wreck from a distance as opposed to seeing just seeing the bits and pieces within viewing range. The wreck also had been underwater for just a few years, so things were not quite as rosted and encrusted as on the Prince Albert. I had my divelight with me and actually penetrated the hull of the wreck. It had all been prepped for divers, but it was a first for me, and exciting.

Every trip I’ve made in my life has been different. I’ll remember this one as my second ocean dive trip with many wonderful dives, but also for the observations I made and things I learned about diving and dive trips.

Allergies and colds

I’d been taught that diving while suffering from allergies or having a cold is inadvisable, or even dangerous. This has to do with the clogging up of sinus cavities that may make it difficult or impossible to equalize pressure in your ears or result in blockages elsewhere. This time I found myself with fairly severe allergies, probably due to the wind that stirred up all sorts of allergens I was not used to. This began on Tuesday and I really did not want to miss diving the rest of the week. So I decided to give it a try.

Amazingly, I encountered very little problem. Equalizing was a bit more difficult (and a bit noisier), but it did not pose any real difficulties. A couple of times I encountered sinus pressure and pain in my forehead right above my eyes. Whenever that happened I simply stopped descent and ascended a couple of feet. This almost always made the pain/pressure disappear and I resumed descent. I was able to do another seven or eight dives, including one below 100 feet without any pain or other issues. If anything, diving felt like a relief from feeling somewhat miserable on the surface.

This does not mean that I recommend diving while suffering from allergies or having a cold. It just means that in my case, it did not mean the end of diving for the week. If anyone finds him/herself in the same situation, I’d recommend finding out what can be done rather than just giving up.

Insects

Insect bites can be a major pain on dive vacations. Roatan’s infamous “no-see-ums” were out in force and three days into our stay we were covered in nasty red bites. This seemed to happen no matter what we did, and no matter how we tried to protect ourselves. While we hacked and coughed from the fumes every time we sprayed arms, calves, neck and every other exposed part of the body, the no-see-ums appeared unaffected and everyone was covered by bites. Nasty red dots that then spread and began itching so much that scratching till things were raw seemed a preferable alternative. No fun.

Interestingly, the divemasters and dockside staff seemed immune and had no bites. I asked our divemaster, Jessie, and he grinningly said his skin was too dark and tough for the bugs. I shopped for a second opinion and found that the locals attribute their relative immunity to their diet that includes fragrant oils and a lot of vinegar. The vinegar supposedly changes the acidity of the body and skin, and keeps the pesky little buggers away.

At times I felt irrational frustration and anger against the bugs. Our beach house was beautifully located and a gorgeous beach beckoned, as did walks along the beach and through the luscious groves. But there was a price to pay in terms of insect bites, and that price simply was too steep. So we stayed mostly indoors.

Clothing

Somehow it seems impossible to ever pack the right clothes. When I lived in upstate New York I used to assume it was cold everywhere else, too, and overpack. Now that I live in sunny California I generally don’t pack things that are warm enough in colder parts of the country. Fortunately, the wardrobe requirements for the kinds of traveling I usually do are modest, and if push comes to shove, there’s usually a Target or Wal-Mart closeby to buy things.

For this trip the weather report had predicted temperatures in the low 80s during the day and low 70s at night, and so I only brought one pair of blue jeans and one long-sleeved shirt. That was not enough. There wasn’t much rain during the week, but it was windy, which means wind chill factor. Sitting on a dive boat in a wetsuit with the wind blowing is a miserable experience. As a result, the local dive shop quickly sold out of Chammyz, the cozy, warm dive and actionwear. They had 20 of them or so the beginning of the week, and they were all gone by Friday.

Dive skins

Almost every serious diver I ever met has been singing the praises of dive skins. Dive skins are ultra-light full-body garments that look like wetsuits but are much lighter. Depending on whom you talk to, they either look like those snazzy high-tech suits worn by Olympic swimmers, or like ballet tights (I think it’s the former).

Dive skins are usually worn in really warm water (85 degrees on up) or under a wetsuit. You don’t really need a full-body suit in such 85+ degree water, but some divers (including myself) like to have their skin covered so that things don’t sting or bite as easily.

On this trip, I bought a dive skin because I simply felt too cold with just the 3/2 mm wetsuit. So now I know what a dive skin does, and does not, do. First, a wetsuit goes on a hundred times easier if you wear a dive skin. No more struggling; the wetsuit simply glides on. However, do NOT expect to be warmer underwater. I wore the dive skin under my 3/2 mm wetsuit on several dives in 78-80 degree water (which, amazingly, feels pretty cold after a while) and actually felt colder with the dive skin than without. I think that’s because of the way wetsuits work. A wetsuit is designed to let in a thin layer of water that is then warmed up by the body. The wetsuit does not easily let the warmed-up water layer escape, and so it acts as insulation and keeps you warm. If you wear a dive skin under the wetsuit, the dive skin sort of disrupts that insulating layer of water and you feel colder. I know, it doesn’t sound logical that wearing more should make you feel colder, but in this case it does. I am not sorry I bought the dive skin though. It looks and feels great, and it serves a number of purposes. It also stows away into a tiny packager that fits almost anywhere. How much did it cost? I paid US$95 for an Akona XL dive skin at the Dockside dive shop at CoCo View.

Taking pictures underwater

I’ve been taking pictures for what seems like forever, and underwater pictures for a good while. Yet, every time I go diving with a camera I am reminded that taking pictures underwater is absolutely and totally different from taking pictures on land.

On land, cameras have it easy. All they have to do is measure the light, determine aperture and shutter speed, focus, and then take the picture. If there isn’t enough light they use the flash to help out. So what’s different in the water?

Well, there is much less light for starters. And whatever light there is acts differently from the surface. Certain colors disappear at fairly shallow depths. Red is gone at 15 feet or so. Orange and yellow soon follow. Which means that everything looks greenish-blue, which looks pleasant enough when you swim through it, but much less so in a picture. Add visibility that is MUCH less than on the surface and hunting for light becomes a huge challenge even for the best cameras. To provide perspective, on land you can often literally see for many miles. Underwater, divers are thrilled when they have 100 feet or so. Even “gin-clear” water rarely has more visibility than 150 feet. And I’ve been on many a dive where visibility was just four or five feet, which is much less than even the densest fog.

As if inadequate light and limited visibility weren’t enough of a problem, there’s so much stuff moving in the water that most auto-focus systems are simply overwhelmed. When just about everything is moving, what should the camera focus on? Fixed focus or automatic spot focus are almost a must for decent pictures, and even then they are far from guaranteed as focusing systems need enough light to do their job.

Add to that the fact that not only is the whole scenery moving constantly, but so are you. Even the most advanced divers seldom remain completely motionless; there are always little corrections, or the surge moves you back and forth. This makes an active, optical anti-shake system pretty much mandatory. Digital anti-shake really doesn’t work as it’s based on increasing sensitivity and shutter speed, an approach that doesn’t work well underwater. Why not hold on to something or sit down? Easier said than done. Many resorts and marine parks prohibit the wearing of gloves to discourage touching coral and plant life, plus the water will rock and sway you anyway even if you were to hold on to something. Sitting or laying down is also not a good idea as it either disturbs plants and critters or stirs up silt and sand, or both.

With so little light most of the time, you need a good flash, right? Yes and no. A flash can do wonders for macro photography, but it is worse than useless in just about any other situation. That’s because a built-in flash will illuminate every tiny piece of flotsam and jetsam producing what underwater photographers call “scatter.” In anything but the clearest water, flash-generated scatter makes most pictures unusable. Now, as far as I am concerned cameras should know that but most don’t. If the camera is set on auto-flash, it’ll use the flash with almost every picture underwater, rendering them useless. So you find yourself in the unenviable position of not having enough light, but also not being able to use the flash.

Many cameras for which underwater housings are available have underwater settings. Problem is, it’s not always clear what they do. The otherwise excellent Olympus Stylus 1030SW I used has “underwater wide 1” and “underwater wide 2” settings, but virtually no explanation as to the settings used. Select “underwater macro” and the camera goes into full 3.6x tele mode for no apparent reason, so by using the special macro setting I actually had to move farther away from a subject than in regular automatic mode. What this means is that you really need to know your camera and all of its controls. And those controls can be different when you use the underwater housing.

And then there are those little obvious things that can trip us. Like forgetting the power supply, memory card adapter, or memory cards themselves. Some items you can buy at your destination, but it’s, for example, hard to find an xD-Picture card adapter for micro-SD cards or some such. In the olden days all you needed was film. Today it’s a whole slew of things that can put your camera out of commission.

Mask defog

There are few things more infuriating that a fogged-up mask when you’re underwater. Everyone has their own special way of making sure the mask doesn’t fog up, ranging from expensive, exotic defoggers to home-grown mixtures to good old-fashioned spit. I remember at least one dive where absolutely nothing worked and my mask was fogged up the whole dive. This time, the opposite was true. My mask didn’t fog once, and it didn’t leak at all either. I’ve come to really love and appreciate my Scubapro Frameless mask and attribute the absence of leaking to its superior design and materials, but why this trip I didn't have any fogging problems at all I do not know (Carol thinks it's because I used the defog stuff she likes). Even if I had, by the way, by now I figured out how to let a little bit of water into the mask and then swirl it around to clear the mask from fogging.

So there, my second trip to Roatan, another great week of diving.

The flight back was uneventful. I’d dreaded another long, hot, crowded flight from Houston to Sacramento in a leg- and elbowroom-challenged Continental jet, but things went fairly smoothly. I ended up sitting next to a guy who turned out to be a scuba instructor and tech diver from Reno. He and his girlfriend had been diving in Belize. He’d read many of the same scuba enthusiast books as I had, so there was lots to talk about, though he was light-years more experienced than I. I must have come across as reasonably knowledgeable as early on in the conversation he inquired whether I was perchance Bruce Wienke, the decompression guru. Anyway, I was surprised how quickly a 4-1/2 hour flight goes by with good conversation.

Posted by conradb212 at 08:33 PM | Comments (0)

December 05, 2008

Milestones

Sometimes it seems that life is a never-ending series of goals. We plan on doing or achieving something, and then work towards that goal. Once we reach a milestone we've set for ourselves it's on to the next one. And so on. It's no different with diving. First it was actually signing up for scuba lessons, then buying my first set of basic scuba gear (mask, snorkel, fins), then that first breath underwater from a bottle of compressed air, then getting certified in Folsom Lake. Then planning for the first "real" dive, the first night dive, the first Nitrox dive, and the first dive in the ocean.

The one problem with achieving goals is that they can leave you feeling empty. You're there, you've done it, now what? I felt that way after I had successfully defended my thesis many years ago and years of study were over. They say that the journey is the reward and that is undoubtedly true, but it's still the milestones that we remember.

Over the relatively brief time since I became interested in scuba diving I've experienced a lot of interesting things and seen many new places. Yet, for some reason the big milestone is seeing sharks. It's been my goal almost since I started. Maybe it's because people almost invariably ask, "Have you seen sharks?" when you tell them you're a diver. Maybe it's more of a primal thing, one ultimate predator meeting the other.

I had the chance to go on the shark trip in Honduras, but somehow I didn't. I had all sorts of excuses. It cost a good bunch of money. It meant missing some of the regular dives. It was a land trip and then a 30-minute boat ride into the open ocean. It was a 70 foot drop off instead of the 30-50 foot drops I prefer. But lots of other people went, so maybe I was just scared.

I am going on another trip there now, and maybe this time I'll see the sharks. It's a milestone in my diving career. If I do it, how will I feel?

Posted by conradb212 at 04:10 PM | Comments (0)

August 29, 2008

Mary's Place

Some dives are adrenalin-pumpers whereas others are relaxing. At the end of the Roatan trip I was at a place where I was able to relax. I knew that my equipment worked fine and my body, too, and that I would not suddenly freak underwater. I also found myself increasingly able to release all tension and hover, simply let go and enjoy the total lack of gravity. I became much better with buoyancy and had to add and drop air to my BC less and less often. I worked on the bad habit of using my left arm and hand to help manoeuver instead of using fins. With one's breathing under control and a total sense of relaxation, diving assumes a dreamlike quality that is quite addictive. Floating weightlessly becomes natural and seems the norm. I concentrated on finning and gliding with slow, fluid and deliberate movements. That not only conserves air and energy, but also keeps you from harming sea fans, sponges, and other plants.

Between the much better buoancy in seawater and my increasing diving experience, I managed to stay clear of plant life and didn't kick up silt or sand. I only layed on the bottom a couple of times, on purpose, and virtually never used my hands to push off. CoCo View does not allow the wearing of gloves, and so the temptation to touch was greatly diminished. I don't think I touched anything on purpose more than once or twice. Some plants and critters sting or burn, and so it's better to stay clear anyway.

Mary's Place is one of Roatan's most famous dive sites. It is a horseshoe-shaped fragment that broke off from the main reef, perhaps during an earthquake long ago. When that happened, a number of deep cracks and crevices formed and you can now dive through those. The cracks are narrow enough to mandate swimming through them single file and make for wonderfully dramatic scenery. At a moderate pace it takes maybe six to ten minutes to swim through the main crevice of the formation. Attendance at a special buoyancy control seminar is usually required before diving Mary's Place and the site is listed as suitable for intermediate level divers on up.

The initial drop-off was at just 25 feet or so on top of the reef plateau. We then dropped over the wall and descended to about 75 feet. I was a bit nervous as I always am with new adventures as we came upon the entrance of the main crack along the wall. It was adorned by beautiful black coral whose branches actually look orange. On divemaster Eddie's go-ahead we went in one by one. I was videotaping the entire swim-through on the SeaLife DC800 camera. Carol was right behind me with the big Olympus digital SLR. The flat, sandy bottom of the cracks was at perhaps 90 feet or so, though I never went deeper than 75 or 80. I enjoyed this dive very much. Mary's Place lived up to expectation, and then some.

The magical traverse between the otherwordly cliffs was over all too soon. At the end there are two exits, one going straight ahead and expelling the diver into the wide, blue ocean with the wall dropping away to the left and right. Divemaster Eddie suggested we take the last left turn that ascended to another exit, one that was wonderfully picturesque and led back to another exit at maybe 60 feet. When I got to the junction I wasn't quite sure which way to turn as the left turn is just feet before the main crack opens into the ocean. It is fairly narrow and goes uphill. I took that one, working my way up to the exit where we all lingered and took in the sights.

What I didn't know at the time was that Mary's Place, on Valentine's Day of 1990, was the site of an open water deep diving record. Bret Gilliam chose Mary's Place because of the near vertical wall with "abyssal drop-off depths." On a single 100 cubic-foot tank of compressed air, Gilliam reached a depth of 452 feet, performed a few math and word problems on a slate to test his alertness at that depth, and began his ascent after six minutes and 20 seconds. He did hist first deco stop at 50 feet, and an hour and 16 minute slater he surfaces none the worse for wear, having answered all the test problems on his slate correctly.

This was, incidentally, my 50th dive and I couldn't have wished for a nicer experience. Or for a better conclusion to a truly memorable week of diving at CoCo View resort on Roatan.

Posted by conradb212 at 12:53 AM | Comments (0)

August 27, 2008

Waves, surge, sharks and night dives

Lakes are rarely rough and so my diving before Roatan had been in calm water, all of it. I really did not know what to expect from the sea. I remember long vacations on the beaches of Italy and Western France and how the surf pounded the beach, sometimes so strongly that a flag was up indicating that there would be no swimming that day. The beaches on the Outer Banks of North Carolina, of New England and the West Coast of the United States can all be rough and forbidding. On the other hand, I've seen gentle beaches with crystal-clear water and white sand on Spain's Costa Del Sol in the late 1970s, and I still wish I could have been diving there.

Diving in the sea is different. I learned that it can be as calm underwater as in a lake or spring. And even if there are some waves on the surface, once you go under it's all still. But that's not always the case. On some of the dives the water was pretty rough down there. What is waves on the surface is surge at the bottom. You get buffeted around in a rhythm and it becomes more difficult to move and control where you're going. That can be a problem when you want to get close to something so you can take pictures but also want to make sure you don't bump into it and harm the plants. Several times I found myself entirely too close to a wall with its rich cover of sponges and all sorts of outlandish growth, and was unable to get away from it without the vigorous use of fins that might have harmed the plants. Sometimes surge is obvious as in when you see the plantlife swaying back and forth. Other times you don't see it, but feel that you're just not going where you think your movements should get you.

In addition, there's current. Here again, things can be deceptive. Sometimes it's very noticeable and you just fly away, other times you just marvel how effortlessly and quickly you can swim just to find that it isn't nearly as easy to go the other way. That can be a problem as you don't want to get separated from your buddy or buddies, and certainly not from the dive boat.

As for sharks, I didn't see any nor did I do the shark dive on my trip to Roatan. I felt I just wasn't quite ready as I was still acclimatizing myself to diving in the sea and learning something new with every dive. With the exception of a couple of barracudas and some groupers, all from a distance, I hadn't really seen any big fish, so starting out with a bunch of sharks in a feeding frenzy seemed a bit much. Some guests did go, though, and as I expected, they felt it was an incredible experience.

Brian, a very experienced diver from Tuscaloosa, Alabama, and his girlfriend Joanne, also an experienced diver, did go on the shark dive organized by a couple of Italian divemasters who run Waihuka Diving Adventures. The dive site they boat their daring customers to is called "Cara a Cara" -- Spanish for Face-to-Face. Brian said they went down along a line to about 70 feet where they stood and sat against a cliff. Shark feed operations use chum buckets full of stuff that sharks like and the local sharks know the routine. According to Brian, once the dinner bell is rung, the sharks, Caribbean Reef Sharks, appear in a hurry and do get into the feeding frenzy you see in TV documentaries. However, they have no interest whatsoever in the divers, just the food in the chum bucket. Divers are allowed to circle around the whole scene. Once the chum is gone, the sharks leave. The whole thing is recorded on video and participants can buy a DVD. I saw the DVD and it was stunning.

Maybe next time.

I did do one night dive. I had wanted to do more, but each day I was just too pooped after three or four dives to gear up yet again. Others went every night. For beach dives, the protocol at CoCo View is that a flashing strobe must be attached high above the bottom on the "front yard" buoy mooring chain. The first diver who goes out must take the strobe and attach it. Each subsequent diver then takes a numbered tag that must be clipped onto the chain. That way everyone knows divers are out there. Upon return, the last diver retrieves the strobe and brings it back in.

We went fairly late and everyone else, including the strobe, were already back. So we took it out again. We waded through the shallow part of the beach, then donned our fins and turned the divelights on. I brought two, my little Scubapro and a somewhat stronger backup. We quickly found an octopus and stopped to watch it. That was easier said than done for me as the lack of vision and visual references made hovering difficult. Carol attached the strobe to the mooring chain when we reached it and then we were off hunting for whatever might come out at night. There were, as I quickly noticed, a lot of curious fish, some of them quite large. It was mildly disconcerting to train my lights into the dark and then see shadows gliding in and out of my field of vision. Carol went off exploring with the Olympus Evolt 330 digital SLR and I stayed close, lighting things for her. We saw and photographed some interesting critters. The uneasiness never left me.

But it got worse. We encountered blood worms that swarm the divelights like angry flies. You'd think worms just wiggle around on the ground, but these pests buzzed around lights faster than anything I've ever encountered on land, and they got into things. Fortunately, I wore my 3mm wetsuit, but I still felt them against my hands, face and ears. I pulled my skullcap down over my ears as far as I could. Those things were an absolute pain and ruined whatever enjoyment I might have had out of that night dive. Yuk! We quickly retrieved the strobe and retreated to the beach. I'll try again to see if I can find the night dive magic many divers talk about.

Posted by conradb212 at 11:32 PM | Comments (0)

August 26, 2008

Contemplations on a day off

There's much joking going on about "Montezuma's Revenge," the type of gastro-intestinal distress that can afflict travelers who are not used to Central American foods and microbiology. No one expects to become afflicted with it, but three days into the trip I woke up feeling not so well. I had been careful with eating and drinking but apparently not careful enough. So it was diarrhea and feeling pretty awful. DAN, the Divers Alert Network, has guidelines on what and how to eat and drink in foreign countries, but I must admit I did not brush up on them before we left. I dragged myself to breakfast but did not manage to eat anything. It was obvious I was not up to diving and so I stayed in my room instead. I had seen a black beach towel laying in the water below the cabana that in the shadow looked just like a ray and so I wrote a children's story named "Ray, the ray" where the beach towel became real. I jotted down impressions about the trip. I dozed. I hoped I wouldn't be out of commission for the rest of the week. It'd be awful to have come all the way down to Honduras to experience ocean diving and then be sidelined by diarrhea.

I took some Imodium tablets I'd brought along and wondered about the practical aspects of diving when you don't feel up to par. Boat rides can be pretty rough and sitting in a rocking boat on top of feeling nauseous to begin with didn't sound too good. And I wondered what would happen if you went diving and had to throw up. I'd read about that and apparently you're supposed to vomit through the regulator without taking it out of your mouth. I hoped I wouldn't have to put that to the test. As for diarrhea, the thought of suddenly having an uncontrollable urge while diving with a wetsuit on wasn't pretty.

I thought about the amazing CoCo View resort and how it came about. I'd been to Central America in the late 1970s and visited El Salvador and Guatemala. Apparently, while I was lounging by the pool at the luxurious estate of my friends in San Salvador in 1978 and played tennis at the Salvador Sheraton, conditions on Roatan were still quite primitive. Roatan is part of the Honduran Bay Islands that also include Guanaja, Utila and a few dozen much smaller ones. The 49 square mile island was said to be discovered by Columbus on one of his later voyages, then visited by Spanish conquistador Velasquez in an episode disastrous for the indigenous Paya Indians who were enslaved and put to work. Roatan became popular with pirates who, together with the British, were a thorn in the side of the Spaniards. Spain essentially demolished the island by 1650 but English privateers returned and used Roatan as a base. Even the notorious pirate Blackbeard was there for a few weeks in 1718. In the 1700s it was a constant back and forth between England and Spain. By 1800, the English brought thousands of revolting slaves from other islands. Those were called the Garifuna and their descendants are still there today. Roatan was considered a British Crown Colony, albeit a rather minor and neglected one, and influential English families from the Cayman Islands arrived. Though the island was essentially English and Scotch, Queen Victoria, against protests from the settlers, turned Roatan over to an only vaguely interested Honduras in 1858. These days, the official language is Spanish, but many still speak English, and most municipalities have English names.

A 1996 report by a writer/diver/developer by the name of Lorenzo Dee Belveal who first came to Roatan in 1966, built Spyglass Hill Resort, and ran it until 1981 just when CoCo View got underway is interesting albeit perhaps controversial reading. A most prolific writer, Belveal described the primitive yet pristine condition of the island when he arrived, with spring-clear water and 200-foot visibility, and what he considers the subsequent overpopulation, loss of safe drinking water due to destruction of the natural aquifer and the resulting danger of water-borne disease. In 1995, Belveal's assessment was "It only took fifteen years for it to complete the circuit from "new and exciting" to "ruined and showing it," and his predictions for Roatan's future were dire.

An account penned by Dennis Foster in circa 1990 describes the island as still quite primitive with barely a runway, not much in terms of roads (read Belveal's The Road for an idea), no telephone system and no reliable central electricity. Yet, by that time CoCo View resort had already existed for a decade, established by visionaries Bill and Evelyn Evans with the help of local and immigrated authorities. The "Prince Albert," for example, was named after Albert Jackson, a local tycoon and entrepreneur who built Fantasy Island across the lagoon from CoCo View in 1989 (view the Sinking of the Prince Albert). Another influential persona, "Doc" Radawski, is a fountain of historical knowledge and now resides at CoCo View. He came to Roatan in the early 1970s and has been playing a pivotal role in the scuba diving community as well as marine archeology and ecological programs geared towards preserving Roatan's natural beauty. I greatly enjoyed his excellent lecture on the history of Roatan.

Fortunately and amazingly, in the afternoon I felt well enough to go diving. I found that I had missed some minor discord on the boat that occurred when a guest who was reviewing the resort for a publication or website requested four full boat dives a day as opposed to two dive site dives and two drop-offs. Drop-offs mean the boat won't take you back to the dock and you have to exit through the beach. At CoCo View that's a long swim in very shallow water, and no fun with extensive camera equipment. So the boat took him to some other dive site and thus was not at the dock when the drop-off divers arrived. Some had left personal belongings on the boat including, in one case, their room keys. That, admittedly, can be annoying and so there were complaints. Divemaster Eddie may have gotten an earful from management over that and was none too happy about it. So he called the group together and discussed the matter in a mature and straightforward manner. This young man will go far.

I later got to talk to Eddie whose blond-streaked hair, very much unlike mine, always looked perfectly towsled and coiffed minutes after a dive. His family came from mainland Honduras when he was three years old. They now own some real estate and a store. Eddie has been working in one capacity or another at CoCo View resort since he was in his early teens. He was a busboy, worked in the kitchen, the dive shop, etc., until he got a chance to get into diving. He started highschool, but still has to finish it. He took a course in English, and his mastery of the language is excellent. He fluently converses in English with an accent hardly thicker than mine. English, Eddie said, is necessary on the island to get a good job. That and computer knowledge. No one else in his family speaks English, and Eddie is trying to get at least his sister to learn it. He's never been to the United States but he has a dream of going to college and study something that relates to his love of diving and the sea. Marine biology perhaps. I hope he gets to realize that dream.

The dive site we visited was called Menagerhea, named or renamed after Rhea's Diving Services, the diveshop Carol managed for a number of years in Tennessee. The seas were a bit rough but I felt just fine, and even better once I was in the water. The site started out quite shallow, then we slowly descended down along a wall. Looking out into the open blue ocean we saw some pretty big fish, including barracudas and groupers. It's fascinating to gaze into the blueness and suddenly seeing a faint dark shadow that then becomes a fish. You can't quite tell how far away they are, or how big. The Menagerhea site is close to shore by the Newman Wall, and so there was quite a bit of surge.

For the drop-off dive I chose the Prince Albert, but this time with a special mission. I took along the Olympus Stylus 1030SW, a 10-megapixel camera that's waterproof to 33 feet without an underwater housing. It's the successor to the Stylus 770SW that we'd taken down to 67 feet at Manatee Springs in Florida with no ill effect. For a while I thought that camera was invulnerable until it did flood at 90 feet in Lake Tahoe when I simply forgot that I'd taken it with me on the dive. I definitely did not want to kill the 1030 as well and so could only take it to the upper parts of the wreck. Still, that meant half an hour between 30 and 40 feet, and a bunch of pretty good pictures -- not bad for a camera that looks just like any other modern little digicam. The visibility wasn't the best, but it took decent pictures.

Posted by conradb212 at 12:06 AM | Comments (0)

August 25, 2008

Prince Albert and green blood

In "Silent World," published in 1953, Captain Jacques-Yves Cousteau describes a new type of fish they had found in the French Mediterranean off Marseille. They'd gone deep and speared a good-sized liche and the fish bled. The blood, however, was emerald green and that was quite unusual. Ever the scientist, Cousteau made sure they'd get this trophy to the surface so they could examine the green-blooded fish. They did and were anxious to show their find to the team, but as they ascended the green blood turned brown, then pink. On the surface the fish was bleeding red like any other. Cousteau probably slapped his head and went, "Of course! You cannot see red deeper than 15 or 20 feet or so." When I read that I thought it was pretty strange. No more. I bleed green, too.

Whatever causes underwater nosebleeds struck me during a morning dive. The boat had taken us out to "Calvin's Crack," a gorgeous though somewhat oddly named dive site that's indeed a narrow crack in the reef (it was likely named after Calvin Bodden, friend of CoCo View founder Bill Evans). It descends all the way from a fairly shallow entrance area at maybe 30 feet of water to an opening to the ocean deep in the wall. The entrance is like a cave or cavern and you go in head-first, but it's not really an overhead environment as light remains visible through the top of the crack at all times.

It is a wonderfully eery experience floating downward between walls of sheer rock to the left and right, from 30 feet to perhaps 80 or 90, with beams of light from the surface shining down from between the cliffs, and air bubbles from divers ahead of you rising in a silvery stream. Diving the crack is like floating through a rugged, narrow canyon with just enough room for a single diver. The sandy bottom of the crack descends until it opens on the side of the wall into the blue ocean at a depth of anywhere from 60 to 100 feet. I'd been nervous again before the dive, of course, but felt just fine going into and through the crack. It was all totally new to me and so I composed myself and finned through, not taking nearly enough time to look around and take it all in.

I exited Calvin's Crack at about 85 feet, with the bottom still well below me. It was over too soon, sort of like a rollercoaster ride at the carnival. The water felt noticeably colder once I emerged from the wall and was floating in the open ocean along the nearly vertical cliffs. Later, when I uploaded my dive computer data into my notebook I saw that the water temperature had dropped all of four degrees, from 86 to 82 degrees Fahrenheit. All thermoclines should be that mild.

Over the next 25 minutes we slowly worked our way along the luscious wall and back up to shallower water. I noticed that the left side of my Scubapro Frameless mask was getting pretty murky with liquid accumulating at the bottom. There is almost always a little bit of water seeping into a mask and it's no big deal once you know how to purge. My Frameless mask is as leak-proof as I've experienced (I have tried out a dozen masks or so) and I rarely ever have to clear my mask to get the water out. I didn't like the murky greenish water and wasn't sure where it came from until it turned red as I ascended and then I knew. Nose or sinus bleed. Looks emerald green at depth. Nothing to be alarmed about, but definitely something I could do without. I cleared out the mask as much as I could before entering the dive boat through the cut-out with the ladder in the bottom, but Jorge, our boat captain, noticed right away and actually looked a bit alarmed. He gave me tissues once I was on the boat and I ended up needing quite a few of them. So that was a pretty good nosebleed.

I decided to skip the morning's "drop-off" dive and head back to the dock on the boat. That gave me a chance to roam around CoCo View resort a bit, look at the dozens of hummingbirds excitedly competing for a spot on one of the sugarwater bird feeders, and check out the well equipped PADI 5-Star dive shop (Dockside Dive Center). I asked the dive master and other authorities about the cause of the nosebleeds and what one can do about it, but no one seems to know for sure. I have no clue what causes regular nosebleeds (which I have rarely ever gotten), let alone ones caused by diving. They call seats high up in a stadium the "nosebleed section," so I suppose pressure has something to do with it. Carol said many divers, including accomplished ones, have to deal with this and that it usually goes away after a number of dives. I sure hoped it'd go away for me.

I did take the afternoon dive (Valley of the Kings), but made sure I stayed relatively shallow, never going deeper than 55 feet. The dive took us along a wall and then over an undulating reef plateau with lots to see. I think I'll never get tired of looking at the plants and sea creatures. I used to think real sponges looked like what my grand parents used in their bathroom. I had no idea they where tube-like structures in all forms, colors and sizes. Gliding through it all you never know what you'll see next. Many sea creatures have adapted themselves to a specific plant, mimicking shape, texture and color so they become nearly invisible against the backdrop of their host. Wonderful though it was, I felt a bit apprehensive after the green blood episode and so wasn't able to relax and enjoy as much as I should have. I did still have a bit of bleeding, but much less, and so I decided I was going to risk a second dive that afternoon. After surfacing and recuperating we asked the captain to take us to the wreck of the Prince Albert.

Not all wrecks are the same, and one sitting in 45 to 70 feet of water in a channel right outside of a dive resort is most definitely not in the same class as one much deeper somewhere in open water. But until I see one of them, if I ever will, as far as I am concerned, the Prince Albert is a real wreck and then some. It is a large iron vessel sitting upright. It was sunk almost 25 years ago specifically as a scuba attraction by the owners of the CoCo View resort. It has many openings to explore and has probably been proofed so it's safe for divers. Then again, it's still a wreck deep underwater and it can look very intimidating. The sheer mass of the wreck is humbling as you weightlessly glide along its coral and sponge-encrusted sides. The water whose clarity can be exceptional at the top of the wreck can dwindle to just a few feet at the sandy bottom. Plantlife has taken over and transformed the massive vessel of steel into a silent reef with dark gaping holes along the sides and on the top. It's all open for exploration without any supervision at all. I didn't have my divelight with me and so could not see what's inside. Not that I would have done so in the first place. Floating in darkness inside a rusted hull does not seem totally harmless. I must assume things are closed off enough so divers do not get lost, but it all did look forbidding and intimidating.

It is amazing how very quickly sealife takes over a sunken vessel. The seafans, sponges, and corrals of all kinds did not seem any different from those that grow on reefs and walls. I thought a wreck would be all mud and rust and sediment, but it's a living, teeming medley of plants and fish, and really quite indistinguishable from a reef. There are large, spindly plants that stick and fan out all over the place as well as the usual variety of sealife large and small. Fish and other critters are everywhere.

I thought of all the books I had read about divers exploring the Andrea Doria or the Empress of Ireland, and how those wrecks claim lives even from the very best. I don't think it's worth risking one's life for a porcellain plate from a sunken ship, but people know the level of risk they wish to take. Seeing the wreck of the Prince Albert gave me an idea of what it's all about. It was very real, very impressive, and a thrill.

Posted by conradb212 at 04:11 PM | Comments (0)

August 24, 2008

First ocean dive

I've had my first ocean dive. It was actually three, an orientation dive in the morning and then two boat dives in the afternoon.

Apparently, no matter what age I am, I get uptight whenever I do something new for the first time. I fell asleep just fine the evening before the dive, and had a good night's sleep, but during breakfast and then the orientation upstairs in the clubhouse I was absurdly nervous. Just like I used to get when I had to give a speech.

We then got geared up and entered the very shallow water at the beach in front of CoCo View's clubhouse. Our divemaster, Melgar, gave an introduction: first we'd swim down an incline, then congregate at the anchor plate of the buoy to demonstrate skills (flooding and clearing the mask; removing the regulator and blowing bubbles), then go past the wreck of the Prince Albert and on to Newman's Wall, then back to the wreck and over to the other side where CoCo View Wall is. That sounded like an awful lot of distance for just an orientation dive, and it felt like it, too, but when it was all over it had taken all of 45 minutes.

I had often wondered what it'd be like to see a shipwreck underwater. I envisioned it as spooky and threatening, sort of the ultimate symbol of human maritime defeat. A ship sinks and goes down to the bottom of the ocean. The image of the water closing over it and it falling has always felt extremely ominous to me.

But seeing the Prince Albert, a 140 foot long hulking former tanker, was not that threatening. Maybe it was the good visibility, or maybe shipwrecks are just one of those things that looks and feels all different once you actually see one underwater. We did not stay and peruse the encrusted wreck of the ship that'd been sunk as a diving attraction in 1985. There'd be plenty of time for that later.

Close to the wreck we saw a school of squid slowly circling in formation. An amazing sight that was. They have those huge eyes and you never quite know which side is the front and which the back. They seem intelligent, very deliberate, and very different from fish that tend to dart around this way and that.

The Newman wall was imposing, and I assume representative for a lot of Caribbean underwater walls. It's far steeper and rockier down there than you'd expect judging by the looks of the geography above the water. Roatan is hilly, for sure, but it does not seem to have the sheer cliffs that drop down many hundreds or thousands of feet. And every square inch underwater is occupied by something -- plants, fish, sea critters of all kinds. This is really what blew me away most. Lake Tahoe has awesome scenery and walls, but it is nearly devoid of life. Here I saw nothing but life teeming all over the place.

I still wrestled with some irrational fears, most of which I attribute to my initial uneasiness with new things. I am aware at all times, for example, of having all that water above me. If anything goes wrong there is simply no margin for error. What would happen if I had a sudden bout of ... something? Would I be able to handle it? Also, I do like to see what's around me, and I get uneasy when the visibility is bad and things go blank. When you dive you don't fall. Gravity as we know it is suspended. But the brain doesn't know that. So it can feel weird to float in nothingness, or turn around and see nothing but open water. But it is not only space; temperature fluctuations can also sneak up on you. You feel your body go cold and for an anxious few seconds wonder if something's wrong. Then you remember: thermocline. I don't mind cold water, but the sudden changes can make me uneasy. That was certainly not a problem in Roatan as the water temperature was 86 degrees and it never got below 84 even at the bottom. Not having to deal with cold water and thermoclines felt good.

Carol had told me many times that managing one's buoyancy in saltwater was much easier than in fresh water. I took her word for it, but it was hard for me to imagine that salt and whatever else is dissolved in ocean water would make that much of a difference. The specific weight between salt and sweet water is very close. However, as I quickly found out, it DOES make a HUGE difference.

In fresh water, where all of my previous dives had taken place (with the exception of that saltwater pool, but that doesn't count), buoyancy is a constant struggle. It is quite hard to consistently stay off the bottom so as not to stir up silt. In seawater, if you have your weights right, that is simply not an issue. I just floated, glided, hovered, flew, without any problem at all. It felt like magic. And it's a good thing, too, because the plantlife on the reefs is far more fragile than I imagined and I sure did not want to harm it.

Diving a reef, I found, is like slowly flying over and through a Pixar landscape. It's like being in "A Bug's Life" or "Finding Nemo," only much more intense and, of course, real. Those guys at Pixar must be divers, I am sure. The diversity and vitality of all those plants is simply amazing: all sorts of sponges and gorgonians (seafans) are everywhere. Some cover rocks, some bulge out, some stick out weightlessly. There's a myriad of different kinds of coral. Fish dart in and out between them in a never-ending fluid dance. Some are lightning quick, some deliberate. The water is a very different medium to live and move around in.

After lunch I experienced my first ocean boat dive. We were on the green boat, the CoCo III. The boats are larger than the ones I'd been on on the Manatee snorkel tours, and the cutout in the center through with you can get back into the boat by climbing up a ladder is fairly unique. Divers sit along the sides by their gear.

The first actual dive site we visited was called "Too Tall Too Small." I am not sure where it got that name. My guess is the resorts get quite creative naming those sites as there are so many. It was a marvelous wall dive, again full of teeming life of all sorts. As I was gliding through this wonder world I thought of the Beatles song "Lucy in the Sky with Diamonds" where they sing of "cellophane flowers of yellow and green," and "newspaper taxis waiting to take you away" and similar. Some said that song was really about acid trips (Lucy in the Sky with Diamonds), but though I have no firsthand experience I cannot imagine an acid or any other drug-induced trip to be any wilder than diving a reef.

The combination of weightlessly floating amidst this unreal, unbelievable underwater world with colors and shapes I'd never seen; hearing myself breathing air from a tank on my back; knowing that I was deep under the surface and really in quite a fragile position, it all adds up to a suspense of reality as we know it on the surface. It makes you think and question things. There's so much down there, and it's all so different from the familiar dry world above. The ocean is huge and endless but also delicate and tender. A single boat anchor carelessly dragged across the reefs can destroy what took decades or hundreds of years to build, and what is home to an intricate miraculous world that is a miracle.

Posted by conradb212 at 11:50 PM | Comments (0)

August 23, 2008

Dive trip to Honduras!

I am finally on my first real dive trip! It's taken me over two years to graduate from those initial checkout dives in Folsom Lake to my first diving experience in the ocean. That's ridiculously long, especially considering that I've been running a full dive website for more than two years, and that I've written this book about diving. But now I am on Roatan Island off Honduras, and tomorrow morning I'll have my first ever ocean dive.

We're at CoCo View Resort on the southside of Roatan. CoCo View is not a resort in the traditional luxury accommodations sense of the word. It's a community of bungalows, cabanas and buildings on a totally secluded penninsula. It's tropical to the max, with flocks of Hummingbirds darting around, palm trees and other lush tropical greenery everywhere. Some of the bungalows and cabanas are directly on the water. Yes, I can actually see the water between the cracks of the floorboards in my room.

Getting to Roatan is easy. It may be a penninsula off an island off mainland Honduras, but all it took was a three and a half hour Continental flight from Sacramento to Houston, and then another two and a half hour flight from Houston to Roatan island. And not in a tiny turboprop, but in a real Boeing 737. Flying along the central American coast line is an experience by itself. There is so much pristine, gorgeous and seemingly uninhabited beach with inlets and islands. Is it yet to be discovered? Is it protected? What's the deal?

Immigration at Roatan airport is a lengthy procedure with stern customs officers handwriting and hand-copying lots of stuff. I am sure it serves a purpose, but hey.... we're just here for a week of spending money and boosting the local economy. It's hot and incredibly humid waiting in line. Our luggage has bright pink CoCo View tags and is being picked up and moved through customs by friendly folks from the resort. We're being greeted and soon sit in a nicely air-conditioned Kia van.

The ride from the airport to CoCo View is maybe 20 minutes and what I see is, on a somewhat less extreme scale, what I remember from a late 1970s trip to El Salvador. Visible from the streets is a weird mix of wealth and poverty, American-style shopping strips and much more modest local stores, corrugated steel covered huts and driveways to mansion and resorts.

The ride ends at a large boathouse from where we're ferried to the actual resort, just a few stone's throws away across a still lagoon, and yet so far from civilization. We get a brief intro from a friendly young American woman who hands out forms and the usual disclaimers. There are two young couples from New Jersey and some guys. How many dives do I have? That'd be 36. How many night dives? Ummm... one. Dive buddy Carol senses my intimidation and volunteers that my one night dive was the mother of all night dives. I remember well. It was. But I am still sure that everyone else is vastly more experienced, and they are a bunch younger, too.

I pick up the key to the cabana on the water and it is sensational, just gorgeous. Hot and humid despite the big room air conditioner, but that's to be expected. I am blown away. Pretty much everyone who comes here is a diver and so instructions on what to do are in the room. We unpack and gather up our gear and walk on over to the dive building and dock. Four boats are there, painted yellow, red, green, blue. We've been assigned to the green boat, CoCo III. They are sturdy vessels that, as I later learn, even have an opening in the center for divers to climb in.

We store our gear in cubbies, then sign in to get weights. They are the old-fashioned solid lead weights. The two couples are here and they seem to know exactly how much weight they need. Me, I tried in the pool and sort of figured I might need 14 pounds. So that is what I get.

I am not sure I want to use Nitrox as it costs $8 a fill or $120 for the week whereas air is included. Carol uses it, and so I make my first three tanks Nitrox as well. We test for oxygen content and pressure, note the data on a sticker on the tank, then deposit our passports at the office. At the signup sheet I see that the Jersey couples have already signed up for the shark dive.

What have I gotten myself into? Will this work out? It's gorgeous here for sure, but what awaits me beneath the surface?

Posted by conradb212 at 07:46 PM | Comments (0)

August 11, 2008

Dogs, tanks, suits and Nitrox

Sometimes you go diving and it's just for fun. Other times you learn a bunch of new things as I found out this past weekend at Lake Tahoe. Instead of Meeks Bay which is usually overrun with certification classes, we went back to the D. L. Bliss State Park just a few miles away from Meeks. That's the site of the (in)famous Rubicon Wall that plunges down from 60 feet or so to a depth of 1,500 feet within just a quarter mile. Unfortunately, the trail from the Callawee Cove parking lot is a plunge all by itself, and quite a pain with scuba gear on. Still, the lure of the secluded beach and the wall were enough to make us go back.

Parking at D.L. Bliss is just six bucks a day, a real bargain when you consider the giant size of the park (it takes a mile on a narrow, winding forest road to even get to the park entrance gate) and the gorgeous vistas. It's a bit like Big Sur with lots of woods and nature. We arrived at the smallish Callawee Cove lot at 9:30AM when you can still pick your spot. As always with diving, the closer to the beach you can get the better.

This time, with the memory of lugging those giant 104-cubic foot steel tanks down (and up!) the steep trail, we brought comparatively tiny high pressure steel-80s. They don't look very manly, those tanks, but on this trip I certainly got to appreciate them. Sure, I only had 80 cubic-foot of air instead of 104, but that was enough, and the big difference in size and weight made this trip about diving and not about scaling what seems like 700 steps up a vertical cliff.

I never really realized before how important picking the right tank is. As much as I had read about tanks, when I bought my own first tanks I got my two used low-pressure steel-95s because Robert at Diver's Cove in Folsom recommended them, and my metallic-blue anodized aluminum 80 because it looked great. The steel 95s are good but I don't think I ever got a full 2,400 psi charge, and when you begin with 2,100 psi or so, there just isn't all that much air in them. The blue alu tank does look great, but it's actually even longer than the steel-95s, so it's quite a handful for just 80 cubic feet of air, and that's before the annoying buoyancy issues of aluminum tanks (I'll get into that!). So I think I'll relegate the pretty blue tank to pool duty, sell the steel 95s, and invest in high pressure steel 100s if we can find them at a reasonable price. High pressure tanks have their own issues (filling time, availability of high pressure fills, etc.) but at this point weight and length of a tank have become important to me. If you routinely have to carry tanks by the valve, having one that you can carry without it dragging the ground makes things so much easier.

But it's not only tanks where there is no substitute for practical experience. The same goes for wetsuits. While I liked the first wetsuit I ever bought, a 7mm Telos, the thing was so difficult to get into that I started all my dives already exhausted. And pulling the recalcitrant material up your arms and legs practically guarantees sore fingertips as the side of the nails dig into the soft parts. The answer there is to get a suit that really fits. My Telos, for example, was a "medium," which meant it fit my 6-foot, 155 pound frame snugly, but arms and legs were too short. No fun.

Well, Carol pointed out that some wetsuits come in "medium-long," though dive shops don't usually carry the size. My new 7mm Scubapro "Form" wetsuit does come in that size and it fits great. It's also made from a material that is super-stretchy and therefore goes on a whole lot easier. Nothing is ever perfect, though. Somehow it must have escaped Scubapro that Velcro grabs this material like crazy. When you pull the velcro off, it rips the surface layer of the wetsuit material. Scuba gear uses lots of velcro, and so it won't be long before suits made of this material look all chewed up. Anyway, I love the suit and we'll see how it holds up.

The water temperature at Tahoe was 68 degrees as it usually is in the summer. However, I knew from prior dives that it gets colder quickly as you go down and so I used my hood and gloves. I had some concerns about the gloves as we took a test camera along, the new DC800 from SeaLife. The folks at SeaLife have this amazing ability to retrofit ordinary digital camera equipment for underwater duty by tweaking the software and adding special underwater modes that go well beyond what consumer cameras with an underwater setting or two offer. A lot of their magic comes from special white balance modes that correct for the way water filters out different colors as you go deeper. They also know that divers do wear gloves on occasion, and so the buttons on their underwater housings are always spaced to accommodate gloves. It may have escaped them, however, that older divers need reading glasses to see fine print and tiny icons, and so that can be an issue.

I had used Nitrox at the quarry in Tennessee, but this was the first time at altitude. I had contemplated the impacts of altitude on diving before, taken the PADI altitude diver class (twice, really), and read up on the subject. It's hard enough to wrap your mind around the logic of altitude diving on air (it's the ratio of the pressure differences between surface and a certain depth underwater that determines nitrogen absorption, and not the absolute pressure!), and it's worse for Nitrox where you essentially have to determine equivalent air depths twice. From talking to various people and also reading bulletin board posts on the matter, it seems that very few really know how it works. It makes no difference, of course, as everyone relies on their dive computer.

It's interesting to see just how much dive tables and dive computers differ when it comes to the real world. NAUI, for example, sells tables for diving at altitude with 32 and 36% Nitrox as well as for air dives. There are two sets of tables, one for altitudes between 6,000 and 10,000 feet and one for 1,000 to 6,000 feet. My dive eventually took me to 64 feet. Rounded up to 70 feet, the NAUI sea level tables would allow for a maximum dive time (MDT) of 45 minutes. The altitude air table cuts that to 21 minutes. That's because diving 64 feet at 10,000 feet of altitude is more like diving 100 feet or so at sea level as far as nitrogen uptake goes. This is where Nitrox comes in handy. Its lesser percentage of nitrogen increases maximum dive time from 21 to 32 minutes with 32% Nitrox, and 37 minutes with 36% Nitrox. So when diving at altitude, using Nitrox increases maximum bottom times when compared to air, just as it does at sea level.

Now how does all that theory translate into what the dive computer shows during an actual dive? Well, at no time did my no-decompression time fall below 60 minutes. And once set to 36% Nitrox, my Uwatec SmartZ also correctly showed an altitude-adjusted maximum oxygen depth of 100 feet. That's about six feet more than at sea level. Most people would expect less, but as far as oxygen goes, absolute pressure matters and so you reach the recommended 1.4 atmosphere partial pressure of oxygen a few feet deeper at Tahoe altitudes.

It's definitely a good thing to plan one's altitude dives, but once you're down there, the dive computer takes over. And at least in my case, maximum allowable dive time was a lot longer than my air would have lasted. I am getting better with my air consumption, but I am still sucking it up at an alarming rate when I get tense, and diving that wall at Rubicon point is still a somewhat scary experience for me.

The beach at Callawee Cove is shallow. You can dive along the rock cliffs and never reach more than 15-18 feet or so. However, swim away from the beach at the point, and there's the wall. Part of it is just a sheer wall, stark and forbidding. Other parts are giant boulders. All in all, it goes from 60 feet or so down to a 1,500 foot abyss within just a quarter mile. Visibility was far less than when we dove the wall last year. We had at least a hundred feet then, but this time it was just 50 or so, as we had already noticed during other Tahoe dives this year. I am not sure why that is; it must be some sort of local phenomenon as I cannot imagine clarity going down by that much within a single year. Tahoe is totally clean and clear, and pollution simply cannot be a sizable problem. Maybe it was ash and dust from all the California wildfires, and that may also account for the lower water temperatures.

Anyway, I never like low visibility, and its worse when there are severe thermoclines. This time we hit two, each gripping one's entire body. At 65 feet it was already down to 50 degrees. I wasn't uncomfortably cold with the hood and gloves, but between the relatively low visibility, the cold, and the menacing face of the wall, I was breathing hard. By now I know that I do not fall when I cannot see the bottom, but it is still a weird feeling. I did not want for it to overcome me, and so when I saw the wall slowly came into view, I swallowed hard and decided to swim along the sheer and near vertical face of the wall. Last time I had gone over it from the top, following Carol. This time, Carol had gone up to the top and peeked over it, feeling "like the Lion King" as she later told me. I swam along the face, breathing hard and hoping I'd soon come to something other than the sheer face. During those two or three minutes it instantly became clear to me why "blue holes" that often have walls that recede as you go down are considered so dangerous. It's easy to freak when there is nothing below you and rock above. Also, at just 65 feet I didn't feel what I suppose was the calming (to me) influence of a bit of narcosis that I probably had felt at 110 feet. In any case, I am very glad I went back to Rubicon Wall. I love those rock faces and giant boulders, but I'd like them that much better in clearer, warmer water.

Nitrox worked well for me, but then again I'd never had a problem with just air. So for now I know that Nitrox doesn't make me feel weird or anything. There's psychology in that. You need to find out for yourself how something makes you feel.

After a two-hour surface interval on the beautiful beach of the cove we did a second dive. This one was just for fun, poking around the rocks and boulders along the shallow shore. It rarely got to be more than 15 feet deep. We took movies with the SeaLife (once in its case, you cannot switch between still pictures and movies, so you need to decide what mode to use beforehand), watched whole colonies of feisty crawdads do their thing, marveled at how warm the fine sand at the bottom was when you stick your hands in it, and just played around.

This second dive was also a lecture in what an impact different types of tanks can have, and how even the same tank can behave differently when it gets empty. On the first dive I had used the high-pressure steel-80 tank and used 16 pounds of weight in the two pockets of my Scubapro Knighthawk BC. For the second dive I switched to my electric-blue Aluminum-80 tank, this time using 18 pounds to make up for the aluminum tank's higher buoyancy. Carol, who generally barely uses any weights at all, had on her new 7mm wetsuit and was on her second dive with the same tank. She doesn't like a lot of weight and dropped two pounds for this dive. As a result of the different buoyancy she now had trouble going down with eight pounds instead of the ten she'd used on the first dive, and so we switched things around again. Having less weight came back to haunt me after I'd used up about 900 psi of air. As we were returning to the beach and I found myself increasingly unable to stay at the shallow depths as my aluminum bottle was getting more and more buoyant, until I signaled it was no use and I had to surface, and so I did. Note to self: tanks that switch from negative to positive buoyancy are a pain.

I listed dogs in the title of this entry. Where do they come in? Well, we had fun watching some Retrievers and Labs play in the water during our dives. But that wasn't why I mentioned it. Like everyone else, I had learned to look up before surfacing so as not to collide with a boat. I did that and none were in sight. But when I came up I bumped into .... a dog. It was a chocolate Lab, and he'd probably been investigating my bubbles. He was just as surprised as I was and quickly doggie-paddled off. Me, I couldn't stop laughing.

Posted by conradb212 at 04:07 PM | Comments (0)

July 24, 2008

Altitude diving class at Meeks Bay, Lake Tahoe

Almost two years ago I wrote how I got certified as an altitude diver at Lake Tahoe. I thought I had been, I really did. But it turned out that I never got my card and my old instructor vanished. So it seemed like a good idea to do the whole thing over again, and I signed up for the PADI altitude diver class with Fisheye Scuba in Folsom.

There really is no separate altitude class in the PADI system. Altitude is part of "Adventures in Diving" and the concepts and things to know are described in one big instruction manual. I bought the 375-page tome, studied, answered the quiz questions and did the knowledge review. I also attended the altitude portion of the class at Fisheye Scuba which took about an hour.

Instructor Kate Fuquay, who is also part-owner of Fisheye Scuba, wanted students to go up to Lake Tahoe the night before the class so our bodies could properly acclimate to the much higher altitude. A bit of research and calling around yielded a reasonably priced motel room, a rare commodity at Tahoe in just about any season. The motel did not have air conditioning and the room was baking hot despite open windows and night time temperatures dropping into the mid-40s. No big deal as thanks to a big fan I managed to sleep anyway.

Meeks Bay is on the other side of the lake and so it was a bit of a drive to get to the camping and resort area by 8AM. The Fisheye crew was already there and so was an assortment of students taking various classes. Meeks Bay actually has two beaches, a small one north of a marina entrance and a larger one south of it. Both have adequate parking close to the sandy beach and both have rest rooms. The larger resort area beach we used also has a nice store for campers and beachgoers, so that's a plus for when you want a drink, snack or a souvenir (I got a handy nautical map of the lake and surrounding waterways).

My new 6-1/2mm ScubaPro wetsuit went on a lot easier than the recalcitrant 7mm Telos I'd become used to fighting with, but it still took me time to don my gear and make sure all was well. We did the buddy check, then gathered around instructor Kate who spent time going through the special considerations of altitude diving as well as the plans for the dives. One advantage of a group this big (there were probably 20 of us all in all) was that we had a couple of non-divers, and so I had someone to look after my 12-year-old son Morgan who'd come along for the experience. He'd brought his snorkeling gear and I was sure he'd have a great time, but he's still only 12 and I wanted an adult to keep an eye on him.

The water was a nice, refreshing 68 degrees Fahrenheit but I had put on my hood anyway, knowing that Lake Tahoe can get quite chilly during a dive. We swam out to one of the buoys so we could descend on its line to the bottom where we'd compare and record the depths shown on our depth gauges or dive computers. That was on the agenda to see if all were altitude-adjusted and whether readings differed or not. I had my Uwatec SmartZ computer on my left wrist and the Timex Helix on my right. At the bottom the SmartZ showed 42 feet and the Timex 41. Close enough.

Lake Tahoe is wonderfully clear and generally has great viz, but a group of mostly novice divers all gathered at the bottom can fix that in a hurry and so we'd soon kicked up enough sand and silt to make it advisable to move on. The bottom at Meeks Bay is sandy and shallow until it slopes away into the abyss at a 45 degree angle. There isn't a whole lot to see and so we swam along the slope at 50 feet or so. Visibility remained marginal for Tahoe and so our initial convoy soon lost sight of each other and split into smaller groups of twos and fours. It's amazing how quickly you can lose sight of other divers underwater. There weren't any boulders here or schools of fish, and so I mostly concentrated on buoyancy, checking my gear and instruments, and watching the occasional crawdad do its thing. Later I noticed that the temperature had actually dropped all the way to 50 degrees at some point and I never even noticed.

Morgan greeted us on the surface, clearly having a good time. We parked the gear at the shore and debriefed. Our assignment for the second altitude dive was to do a full dive plan, adjusted for altitude, pressure groups and all. Here's what Carol and I came up with:

Our first dive had been to 50 feet at Tahoe altitude of 6,230 feet. The 50 feet translates to a theoretical depth of 65 feet at sea level, so we round up to 70 feet. Our first dive was 29 minutes, so after that first dive we were PADI "N" divers. We then had a surface interval of 2:20 hours, and that brought us down to "A" diver status.

Our dive plan for the second dive was to go to 50 feet again. That again translated to a theoretical depth of 65 feet at sea level. We rounded that up to 70 feet, and found that as "A" divers with a residual nitrogen time of five minutes, that left us with an adjusted bottom time of 35 minutes.

That was that, and we conducted the dive in accordance with the plan. On the second dive I used my compass to navigate to the northern edge of the beach where the underwater scenery was more interesting. We saw some of the huge boulders that had fascinated me on prior dives at Meeks. We swam around and between them, all at non-intimidating depths of just 30 to 40 feet or so. It was a fairly long underwater swim back to the beach, and I used that to once again practice buoyancy at shallow depths where staying level is most difficult. Once you reach eight or ten feet or so, it's all too easy to pop up like a cork and you don't want for that to happen. Constantly correcting by adding air to the BC and then discharging it again is no good; you need to learn to achieve buoyancy by changing the average volume of air in your lungs. Carol barely ever needs her ScubaPro Ladyhawk BC's assistance to maintain buoyancy, and I am getting better at it myself.

We were done diving by two o'clock in the afternoon or so, then headed for lunch/dinner at Rosie's Cafe in Tahoe City. Rosie's alone would have been worth the trip with some of the best Key Lime pie ever, but we also needed to let the residual nitrogen escape from our systems before we tackled the 7,400 feet summit on our way back.

This wasn't the greatest diving ever, but it was fun and I finally have that altitude card in the bag. Not that the card matters. Diving matters, the preparation and anticipation, the people you meet, everything about it. I love it.

Posted by conradb212 at 03:40 PM | Comments (0)

July 23, 2008

Diving at altitude revisited

As we've all been taught in Scuba class, the laws of messieurs Boyle and Dalton describe how air pressure and density, respectively, vary when we dive, and that of Mr. Henry how gasses get absorbed in liquids and tissues under pressure. Nitrogen absorption and release rates directly affect the no-decompression bottom times and are therefore extremely important to divers. The whole pressure picture changes at higher elevations because the air is thinner at altitude.

What we learn in Scuba class always assumes that the pressure at the surface is one atmosphere, or 14.7 pounds per square inch. Course materials then show how a certain volume of air is compressed to half at a depth of 33 feet because the additional pressure of the water on top of us adds another atmosphere, or 14.7 pounds per square inch, for a total of two atmospheres, or 29.4 pounds per square inch. At 66 feet the same volume of air is subjected to three atmospheres and has shrunk to one third of its original surface volume. Conversely, if you blow a certain amount of air into a balloon at a depth of 66 feet, that volume will double once you get back up to 33 feet, and triple at the surface. This is an essential part of understanding diving physics.

However, does this still hold true at altitude? Let's think this through with the example of Lake Tahoe, which is at 6,230 feet above sea level.

At first sight, it would seem that once you are fully acclimated to the Lake Tahoe altitude level, theoretical and actual depth should be the same. At Tahoe you start out at a surface air pressure of roughly 0.8 atmospheres. If you then dive down to 99 feet you'd add another atmosphere's worth of pressure each 33 feet, for a total of 3.8 atmospheres. Then you go back up to the surface where the pressure is once again 0.8 atmospheres. So the pressure difference betwen surface and 99 feet is three atmospheres. At sea level you'd go from 1.0 atmosphere at the surface to 4.0 atmospheres at a depth of 99 feet, and then back up to 1.0 atmospheres, for the same pressure difference of three atmospheres. If anything, when diving in Lake Tahoe you have less total pressure on top of you at 99 feet than at sea level (3.8 ata instead of 4.0 ata) where you'd reach 3.8 ata already at 93 feet. So why then do the altitude tables show that 99 feet at Tahoe corresponds to an ocean depth of about 125 feet and not 93?

The answer is that while the math in the above paragraph is correct, it does not address the problem we're trying to solve. The problem is the uptake of nitrogen, and that means we need to think in terms of pressure ratios and not pressure differences. At sea level, the pressure doubles at 33 feet compared to the surface, triples at 66 feet, and quadruples at 99 feet. Now look at Lake Tahoe where the surface pressure is only 0.8 atmospheres. That corresponds to 26.4 feet of water. So when you dive Lake Tahoe, the pressure doubles at 26.4 feet, triples at 52.8 feet, and quadruples at 79.2 feet. This means that as far as nitrogen ongassing and offgassing goes, you need to divide actual depth by surface pressure to arrive at theoretical depth.

That's because in Lake Tahoe, four times surface pressure is reached at 79.2 feet whereas at sea level four times surface pressure is reached at 99 feet. Henry's law says, "At a constant temperature, the amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid." The way gasses dissolve and expand in liquids and tissues in the body is very complex, but if for simplicity's sake we assume that nitrogen bubbles expand as we ascend to the surface, those bubbles will expand to four times their size from a 79.2 feet dive in Lake Tahoe and from a 99 feet dive at sea level. That is why we need altitude conversion tables (click here for an example of such a chart.)

Below is a table that shows what I call "altitude nitrogen atmospheres." The colored lines show what depth surface pressure multiples correspond to at various altitudes. If you look at the purple line you see that as far as dive tables go, a 132 feet dive at sea level corresponds to a 110 feet dive at 5000 feet altitude and a 98 feet dive at 8000 feet altitude.

It should be obvious by now that altitude conversion tables are used to stay within safe decompression limits. So they handle the nitrogen side of things. But what about oxygen? That's an entirely different ballgame. As anyone who has taken an Enriched Air Diving, or Nitrox, class knows, high oxygen partial pressure can become a problem. Oxygen toxicity can occur when oxygen partial pressure exceeds certain values. This can lead to convulsions and loss of consciousness, and thus quite possibly drowning. The recommended oxygen partial pressure limit is 1.4 ata. The 1.4 ata limit is used by Nitrox divers to compute the "MOD," or "Maximum Operating Depth" of a Nitrox mix. The formula used to compute the MOD is:

MOD = (1.4 / oxygen percentage x 33 ) - surface pressure in feet of water.

If we dive EANx32 (32% Nitrox) at sea level, the MOD is 111.38 feet. But what would the MOD be if we dive 32% Nitrox at Lake Tahoe where the surface pressure is only about 0.8 ata? The answer is 118 feet! Yes, the MOD for diving EANx32 at that altitude is actually 6.4 feet deeper than at sea level. In fact, those 6.4 feet apply to all Nitrox percentages. That's because oxygen toxicity depends on pressure and not on pressure ratio.

That creates an interesting situation: As far as pressure goes, 99 feet in Tahoe is only as much as 93 feet in the ocean. But as far as nitrogen uptake goes those same 99 feet are like 125 in the ocean.

If we dive air, oxygen toxicity is rarely an issue. At Lake Tahoe levels, an air diver would not reach the 1.4 ata partial oxygen pressure level until a depth of almost 200 feet, far deeper than the recommended recreational diving depth limit. For Nitrox divers, however, the MOD can become an issue. At Lake Tahoe altitude, the MOD for a diver using 36% Nitrox is about 103 feet, and that is actual feet, not altitude adjusted feet.

The table below shows altitude-adjusted MOD levels for air as well as Nitrox with oxygen percentages between 30 and 40 percent. Again, the MOD at altitude gets deeper because the surface pressure, converted to the equivalent of feet of water, gets less and less.

But what about altitude adjustment for Nitrox divers? Can they use the same altitude tables? Not directly. Nitrox divers know that in order to use regular dive tables, we need to first calculate the equivalent air depth, or EAD. The formula to compute EAD is:

EAD = (( Partial Pressure Nitrogen / 0.79 ) * (depth + 33 feet)) - 33 feet

You can generate Nitrox Equivalent Air Depth tables in a spreadsheet program with this formula, then use those values to generate a second table that shows Equivalent Air Depth for a given percentage Nitrox at a given altitude, and then use those twice adjusted depths to look up maximum no-decompression bottom times in standard dive tables. What you'll find is that using Nitrox at altitude almost cancels out the effect of altitude: At altitude the equivalent ocean depth is deeper than the actual depth as far as nitrogen goes. But with diving Nitrox the equivalent air depth is always shallower than the actual depth as far as nitrogen goes. Depending on the altitude, diving a certain mix of Nitrox means you can use the standard no-decompression sea level air tables. For diving Lake Tahoe, for example, using 34% Nitrox gives you about the same bottom times as diving air at sea level.

I should also mention that NAUI has plastic dive tables for EAN32 and EAN36 both for altitudes between 2,000 and 6,000 feet and 6,000 and 10,000 feet. The tables are based on the Reduced Gradient Bubble Model and show maximum dive times for the initial dive and a second dive. They are fairly basic and probably include a good deal of safety.

Finally, it's essentially all moot as no one is using dive tables anymore anyway. The dive computer does it all, and almost no one knows how theirs works. That's why I felt a need to figure out how it all fits together. It's still good to know these things. Thanks also to Brian at diverssupport.com for helping me understand all these concepts.

Disclaimer: Although I am fairly confident in my math and checked my findings and results against a number of authoritative sources I do not claim all of this is correct and no one should base their dive plans on what I wrote here.

Posted by conradb212 at 04:01 PM | Comments (0)

June 29, 2008

Full face mask and saltwater

Yesterday I got to experience a new piece of scuba equipment, a full-face mask - and also do my first dive in saltwater. Unfortunately, this all sounds much grander than it was. It all took place at a party at the wonderful home and pool of diving friends. One of the group had brought her full-face mask together with BC and a full tank of air so anyone could check it out. And the gorgeous pool was a saltwater pool, so at least technically I can now say I have been diving in salt water. I know the particulars of this initiation into salt water will only add to the teasing I must endure for having done all of my dives so far in sweet water.

Anyway, the full-face mask was interesting. I had always viewed them as professional equipment beyond the reach and realm of recreational diving. In the "masks" section of our scubadiverinfo.com website I described full-face masks as follows:

"Full face masks protect professional and advanced recreational divers in polluted water and from stings, also allow verbal communication, and alleviate cramps from having to bite on a mouthpiece for long periods of time. They are also warmer in very cold water, and the chance of the mask getting knocked off accidentally is much lower. Full face masks are also referred to as "Jack Browne" masks in recognition of the Desco engineer who came up with the protytpe design of a full face mask with an integrated air supply attachment."

In practice, the full-face mask first looks a bit intimidating. It's large and it has a fairly elaborate strap system. The second stage is built into the mask, so there is no separate mouthpiece. You don't bite on one either. You simply put the mask on, get your hair out of the way, and you're all set. You still breathe through your mouth. The nose is kind of blocked with a rubber piece. BC inflation works the same, with the usual up and down buttons and there was the usual backup second stage, though I am not sure how you'd use it with a full-face mask.

Go under and it's an entirely different experience.

The view is panoramic, and much more so than with any conventional mask I've tried, and by now I've tried quite a view different designs. I wish I could remember the make and model of the mask as, from the looks of it, not all full-face masks offer this panoramic view. As is, this one certainly stood out.

Breathing feels totally natural. It's through the mouth, but not having a mouthpiece to bite on is a huge advantage in my book. Most mouthpieces chafe on my gums or my jaw gets tired from the mouthpiece forever pulling this way or that.

Equalizing your ears is a bit different. The mask did not have the separate nosepiece I use to pinch my nose and blow against it to equalize. The advice was to either move your jaw from side to side or some variation of that, or to move the mask up to block the nose inside as it pushes against that rubber piece in the mask, and then blow against it. I can't remember exactly how I did it, but it was no big deal and certainly not a problem.

Since air flows inside the mask, there is no mask squeeze and you do never have to equalize pressure inside the mask. That's never been a problem for me, but some people forget to do it, sometimes with annoying consequences. All in all, not having to worry about it is nice.

Another big issue for me is mask fogging. I've tried just about every trick to keep my mask from fogging and it does it anyway. This is a real drag. I mean, you don't go diving to see a wondrous underwater world only to see it from behind a fogged-up mask. Sure, you can let some water in and swirl it around the lens occasionally, but that's hardly a satisfying solution. The full-face mask -- at least the one I tried -- did not fog up at all. I suppose it's because of the airflow. It's wonderful not to have to worry about that.

And then there is mask leaking. I was wondering how such a large mask would do. After all, the perimeter of the seal is a lot longer than that of a conventional mask. Amazingly, not as much as a single drop came in. Maybe that's again because of the positive air pressure. If the pressure inside and outside of the mask is the same, water won't come in.

As listed above, there are other reasons to wear a full-face mask. One is to be able to communicate with dive buddies who also wear a full face mask with communications gear, and with the surface. Since you don't have anything in your mouth you can talk, and an integrated microphone then picks it up. I didn't have the battery pack that powers the comms gear and so could not see how well it works.

As for the saltwater pool, it wasn't nearly as salty as I expected. It was also absolutely crystal clear and clean. I'll have to look into it for my own pool.

Posted by conradb212 at 04:38 PM | Comments (0)

June 20, 2008

Quarry Diving

I finally got to dive again and this time it was in a quarry.

Quarries start out as open-pit mines where rocks and other materials are extracted. Once the quarry is no longer used it may fill with water and become a great place for diving. The place I went to is Loch Low-Minn near Athens, Tennessee, a 10-acre lake in the midst of 100 acres of wooded land. Check the web and you find it listed as a McMinn County Highway Department quarry that yielded crushed limestone for concrete and roads in the early 1960s. Its use as a scuba facility came about when a couple by the name of Rick and Stacy Low purchased the quarry in 1996. They named the place Loch (Scottish for Lake) Low (for their last name) Minn (for McMinn County). This quarry is quite popular and has been featured in Dive Training Magazine a couple of times. The owners live on site and take good care of the grounds and the facility. Unlike many quarries, this one has a good number of scuba-related attractions. There are two wooden diving platforms, floating gates for buoyancy training, a navigation course, and any number of sunken artifacts ranging from statues to a Lock Ness monster to funky items like a toilet and such. There is also a large diameter tube to swim through.

Depending on the water level, Loch Low Minn can be as deep as just over 80 feet at the center of the lake. I'd been told that visibility is quite good for a quarry, resulting from the three springs that seep into the lake and all the vegetation that filters run-off from around the lake.

We went there mid-week with a couple of students that had to complete their open water certification. The quarry owners were not there, but had left the big rolling entrance gate unlocked for us. The quarry itself is completely hidden. You don't see it until you drive over an incline and then there it is, a still body of water nestled into rocks and woods. There's a beach and a wooden deck with benches for divers to prepare. A bunch of catfish and a few bass swam around, obviously expecting to be fed.

It was quite hot and humid and I dreaded donning the wetsuit, but my new 7mm Scubapro went on a lot easier than my old 7mm Telos. For one thing, the Scubapro is a medium-long and a better fit than the medium Telos with its short arms and legs. For another, the Scubapro's material is stretchier and softer. It'd been a while since my last real dive and I didn't want to embarrass myself in front of two students, so I prepped my gear slowly and methodically, making sure I didn't forget anything or do anything stupid.

The water felt wonderful, with a surface temperature in the 70s. Carol spent some time talking to her students about the dives ahead and the tasks they had to complete: buoyancy control, emergency free ascents and diver rescue. Then we went down, heading for one of the diving platforms.

As almost always, I had a few minutes of nervousness. Visibility was somewhat less than I expected, and there were rather dramatic thermoclines. The quarry bottom slopes away steeply from the beach and so we soon found ourselves in fairly deep water. I saw the bottom below me disappear, making me feel as if I hovered over nothingness. Then we hit one of the thermoclines that gripped and chilled my body. There was a minute or two when I had to fight a sense of panic ('what if I something went wrong with me?' 'what if I faint?') that urged me to head for the surface. It was over soon and I felt okay again, but the thought of something happening while underwater is not pleasant and I hope I'll never find myself in such a situation.

We soon reached one of the platforms and Carol went through the checkout dive drills with her students. I had the Olympus 770 with me and took pictures of them. Then I saw some of the sunken artifacts I had been told about. I went exploring but the visibility was such that the dive platform quickly disappeared from view. I did not want to get separated from the group and returned before I completely lost sight of it.

Exercises done, we all resurfaced. Carol debriefed the guys and then we set course to the far end of the quarry where we hoped we'd spot some of paddlefish that had been released into the quarry a couple of years ago. This gave the guys an opportunity to learn about compass settings. When asked how they'd reverse the course once we were there, they promptly made the beginners' mistake of trying to visualize what was opposite the original compass reading instead of simply adding 180 degrees. That explained, off we went.

Even though there wasn't anyone else in the quarry to stir up silt, visibility remained fairly low and I realized the value of Carol's bright-yellow fins that made her harder to loose than had she worn standard black ones. As we approached the other end we began seeing slender horizontal shapes in the water -- paddlefish. They seem to be curious enough to check out divers but they don't come close, so I never saw one clear enough to take a picture. While Carol and the guys hovered to look at the paddlefish I decided to drop down to see where the bottom was but at around 40 feet it already got pretty cold dark and I lost sight of the group, and so I ascended until I was at their level again.

Carol then took the lead again and guided us close to the rock wall at the far end. For all practical purposes, it looked like a wall dive. It may have only gone down to 60 or 70 feet, but with the limited visibility it was easy to imagine being in a much larger setting. On we went and back into open water where we swam through a series of hovering PVC pipe shapes. It felt like being in a video game where you got points for flying through a series of gates. The shapes, of course, had been deployed to practice buoyancy. I had hoped we'd also be able to swim through the corrugated metal pipe laying near one of the diving platforms. I had seen it on video and felt it was a clever simulation of an overhead environment without actually being one, but it was on the other side of where we emerged and by now we were at the end of the checkout dives.

We checked remaining air with Carol, needless to say, having used barely more than half of us heavy breathers. Oh, this was also my first time on Nitrox. Since I hadn't brought any scuba gear except my trusted Scubapro Frameless mask I was using borrowed gear. The BC, fins and gauges all worked fine for me, except some chafing on my gums from the different second stage mouthpiece, but I was wondering whether I'd feel a difference diving 40% Nitrox. I didn't. A couple of times I felt a bit like one does after hyperventilating on purpose but I could be wrong. I felt no different after surfacing than I usually feel after a dive, but we'd never gone deeper than 40 feet and total dive time had been just under an hour, so I'll reserve judgement until a longer, deeper dive.

Diving the quarry was fun. It's a very peaceful place with nothing but nature. Before we left we fed the very tame catfish and the pesky bass that always darted between the catfish and snapped away the food from them. I want to go back and have some more time exploring the various stuff placed on the bottom, and also the rock wall on the far end. I am pretty sure I'll get a chance.

Posted by conradb212 at 02:37 PM | Comments (0)

May 06, 2008

Warm-up in the pool

A pool does come in handy for checking out gear and seeing if you still remember how it all works. Once the water had reached 68 degrees Fahrenheit at Dim Cove (the name I have given my pool), I felt it was high time to get wet again after so long. So I pulled the whole setup out of the closet, hoped I had not stashed away some vital part of the gear in some place I now would not remember, and wondered just how I had managed to collect so many masks that in all likelihood I'd never use on a real dive.

Getting the gear out reminded me once again that scuba is equipment-intensive. And almost all of it is needed for a dive. Another good reason to keep it all in one place. A complete set of my stuff is in a large travel bag that I bought at CostCo for just this purpose. It's not a scuba bag, but perfect for the task. I hope it'll hold up to the abuse of many more airplane trips. Things are already beginning to fray a bit here and there. That's probably the difference between a $40 bag and one that costs hundreds.

I was also reminded again just how heavy those tanks are as I shlepped one from my garage through the house and into the backyard. Sure, my steel 95s are monsters and Carol forever advocates the use of smaller and handier tanks for regular dives, but there's just a huge difference between the effortless way happy, smiling divers carry their tanks around in movies and commercials, and how heavy the beasts are in real life. Every time I pick one up I think of cave divers with their doubles, or the deep divers who carry and clip on five or more. Maybe sometime in the future materials science has advanced to a point where compressed air containers, if they are necessary at all, will weigh a fraction of what they do today and people will look at today's gear with the same mix of awe, reverence and amusement we peruse a medieval Knight's suit of armor.

I was pleased that I still remembered how to get the gear assembled. No mistakes there. I know, this must seem trivial to seasoned divers but -- alas -- I am not yet one of them. And I swear, one of these days I'll even learn how to put on my fins more or less elegantly. As is, watching me put them on must be comic relief and raise doubts in onlookers' minds as to my suitability to go under.

But go under I did, and it was great to blow bubbles again. Everything worked fine and, as always, my 12-year-old son had fun looking down with his mask and snorkel and playing with my bubbles. He also practiced his underwater photographer's skills with a Casio in an underwater case. I let him breathe through my regulator just below the surface while I used my AIR2 backup. That's when I noticed a minor annoyance: the nylon tie that secures the mouthpiece of the AIR2 stuck out in the wrong position, poking me in the lip. No big deal, but I always get a bad feeling when factory-authorized service on a potentially life-saving piece of equipment is not done quite right. I mean, if the tie is put on wrong, am I totally sure everything else works okay?

After the 35 minute dive (if you can call practicing in a backyard pool a dive) I was reminded that the end of a dive is really not the end of a dive. That comes only after everything has been taken off, rinsed, put somewhere to dry, and then finally stowed away in its proper place.

Now that my son is old enough to take a scuba class himself, I find myself wondering if I think he's ready for it, and whether I'd be scared letting him dive. I know it's a parent thing to worry, and I'll let him decide if he wants to and when he is ready.

Posted by conradb212 at 02:53 PM | Comments (0)

March 31, 2008

Free diving

When I think of diving, I think of breathing underwater. But most of us dive long before we learn how to use Scuba. When I was a kid, diving to me meant getting to the ten-foot bottom of the public pool, and it made my ears hurt. For a while I practiced breathholding and timed myself. I can't remember how long I managed to go without taking a breath, but it seemed respectable to me back then. I never did learn how to equalize my ears free diving. At Three Sisters in Crystal River, Florida, a sharp pain in my ears kept me from going deeper than eight or ten feet or so. Yet, free divers go much, much deeper than that.

I just finished reading "The Dive -- A Story of Love and Obsession" by Pipin Ferreras. It's the story of a Cuban free diver who set record after record together with his wife, Audrey. A fatal accident killed Audrey during a dive to 170 meters (558 feet) and the book recalls Ferreras life and is also a tribute to his wife. Earlier I had read "The Blue Edge" by Carlos Eyles, also a man who pretty much dedicated his life to free diving, albeit for different reasons. But whether it is records, spear fishing, or just being one with the sea, it is hard for me to imagine how it is done.

Scuba and free diving both take place in the water, but beyond that everything seems different. Scuba dives can take an hour or more. Free dives a couple of minutes or maybe three for accomplished free divers. Scuba is slow and measured movement; free diving means darting down and back to the surface. Scuba means dealing with the gas laws so as to avoid embolisms, narcosis, the bends; free diving has none of that as no additional nitrogen is introduced into the body.

Competitive free diving, of course, has its own rules and governing bodies. There are different categories. In "Constant Weight" the diver follows a line to a certain depth and then swims back up, all on his or her own power. In "Variable Weight" the diver uses a weighted sled to go down, then swims back up. In "No Limit," the diver uses a sled to go down, then inflates an airbag at the bottom and holds on to that to get back to the surface. The depths reached are almost unimaginable. How can they do that?

Apparently, in free diving the rules are all different. With no compressed air to counter-balance the enormous water pressure, the lungs and other air cavities inside the body compress enormously. Conventional equalization of the ears and sinus only goes that far; beyond a certain depth the divers do "water equalization, " i.e. they let salt water into the sinus system in a practice that is described as entirely unpleasant. And another phenomenon takes place when a "blood shift" keeps the lungs from collapsing. It's a residual from ancient times perhaps, from our genetic past, but it works (not that I'd ever want to experience it).

The kind of free diving described in "The Dive" requires extensive planning and preparation. Safety divers on scuba are deployed at regular depth intervals, including the bottom. In those extreme record attempts, that means a diver has to wait at almost 600 feet on Trimix. Breathing gas goes very fast at that depth and it's clear that timing is everything. Once the safety divers are down, the free diving attempt must be made exactly on time. And even so, the deeper safety divers won't be back on the surface to partake in the celebrations as there are hours of decompression time.

Wherever there are records and titles, there are politics and competing agencies and bodies, and apparently that's no different in free diving. In his book, Ferreras describes his life and career, and his intense personality that more or less made him an outcast. Already relying on his own certifying agency, after his wife died in her record attempt he came under intense criticism. One of his own crew wrote a book accusing Ferreras of negligence and wrongdoing.

Knowing my tendency to get deeply involved in topics that interest me, I promised myself not to start research on free diving after I finished the book. But in this day and age that's hard to do. Wiki provides an overview, and Audrey Mestre's final dive is right there on YouTube. Yes, the sled's camera recorded how she is trying to inflate the lift bag at a depth of 558 feet, and it won't inflate. You can watch the whole thing.

Posted by conradb212 at 03:37 PM | Comments (0)

March 26, 2008

Mark Fyvie (1972-2008)

People die every day, by the thousands. From natural causes and from accidents. Unless a death happens in our families or we are confronted with it in some other way, we barely notice. Even the gruesome stuff we see on television or read in the newspapers doesn't really affect us. This only happens to other people, not us. But every once in a while a death does affect us. It can be a celebrity, like Princess Di or Steve Irwin, the Crocodile Hunter. And sometimes a death affects us just because we can somehow relate, through some connection. That's what happened to me when I read about the death of Mark Fyvie. He died on March 10, 2008 inside the Ginnie Springs cave system in Florida.

Running the scubadiverinfo.com site, I get almost every diving-related accident notice via Google news. I don't post them but file them away. It makes no sense to highlight just the danger and the bad things that can happen. Life is dangerous, even one's bathroom where most domestic fatalities occur. I don't see Better Homes & Gardens Magazine report on that very often. It's not necessary.

I first heard of this accident after Carol's certification trip to Ginnie Springs. A cave diver had died the week prior. He had been deep inside the cave system. There had been silting of the system as a result, it was said, and apparently the diver had gone in there by himself with experimental rebreather equipment. I looked it up on Google News and found just three references to it. Compared to the international coverage of the shark-related death during a shark feeding trip, that's a virtual news blackout. In fact, it was just the Gainesville Sun and the local High Springs Heralds that reported at all, or at least that is what Google picked up.

The reports were brief, but what caught my eye was that this was a diver from my native Switzerland. His name was Mark Fyvie, and the paper reported he'd been diving alone, entering the Ginnie Springs underground and underwater caves through the Devil's Eye entry just past noon. When he had not returned by 9pm, another diver by the name of Corey Mearns went looking for him, and Mark Fyvie was found 3,800 feet into the system. The IUCRR (International Underwater Cave Rescue and Recovery) non-profit posted a new thread on the cavediver.net forum entitled "Fatality beyond the Hinkel" in the afternoon of March 11. The report said the diver had used a side mount/no mount rig for passage through a suspected new lead. It was reported that an IUCRR recovery team brought out the body at 9AM on March 11.

I then searched through Tages Anzeiger, the big local newspaper in Zurich, Switzerland but did not find a mention. However, I quickly found Mark Fyvie's website and this is where everything became very emotional. Zurich is my hometown. I grew up there. Zurich Divers, which he started and ran, was Mark Fyvie's diving homebase. His personal site was not in German but in flawless English, which surprised me. I can usually tell translations from German into English, but his English was perfect.

I saw Mark's credentials. He'd been diving since 1993 and a diving instructor since 2000. He had almost a thousand dives to his name. He was a PADI IDC Staff Instructor, an Emergency First Response Instructor Trainer, a DSAT Tec Trimix Instructor, a DSAT Gast Blender Instructor, and an IANTD Technical Cave Instructor. He was also certified as a Closed Circuit Rebreather cave diver, Trimix diver, cave scooter diver, and specially trained on the Megalodon rebreather. So Mark was certainly no noob or amateur. A look at Mark's diving highlights is a trip around the world. He'd been diving and cave diving all over the place, with extensive cave diving, sometimes weeks at a time.

Mark reported on a two week dive trip to the Ginnie Springs area where they'd penetrated 3,800 feet, past the Hinkel restriction. In April of 2007 he did his Megalodon training with a true diving legend, Jill Heinerth of RebreatherPro.com, and Jill was highly complimentary of Mark both as a person and as a skillful diver. Mark himself, on his site, was completely aware of the pros and cons of rebreathers. "Some people who dive rebreathers think that once you buy one you must do every single dive with it." Mark wrote, "I don't agree at all. A CCR is a dangerous device that could kill you at any time, why take the risk of using one on a simple dive that could be done more safely with open circuit?"

Another entry from November 2007 describes a full month of cave diving with the Megalodon rebreather in the Americas. This is where he got his CCR Cave and CCR Trimix certifications and also descended down to 272 feet in Eagle's Nest. He was enthusiastic and wrote, "Now I realise what closed-circuit rebreathers are for - it's totally changed the way I can dive caves." He went on to say, "The bad part is finding a dive buddy for this kind of diving. Even in cave country it's tough and I had to do most of the dives alone. ... Now, feeling rather limited by the duration of my CO2 scrubber, I purchased a new radial scrubber, which should easily be able to handle durations of up to ten hours. I can't wait until my next trip in February."

Again I was surprised by the consistently high quality of his English, then found that Mark wasn't Swiss. He'd been born in South Africa, then had lived in New Zealand, Australia, England, Germany and finally Switzerland. He was truly an international citizen, always traveling and exploring new things and places. Switzerland was not going to be his final destination and even after having been away from my native country for over 30 years, I chuckled at Mark's comment that he yearned "for a place where he can shop on Sundays, take a shower after 10pm". It's true. Your neighbors may call the police if you take a shower after 10pm, shops are rarely open, bars close early and at last in my days, you had to register with the police if you moved from one neighborhood to another.

What made me cry was another part of his website. It was about his wedding. He had proposed to his sweetheart and they were going to get married on September 6th of 2008 in Venice. Mark had it all planned out, described every step. He had his whole life ahead of him. It is just so very sad.

At this point I was abundantly clear that this was not just another reckless diver who didn't know what he was doing. This was an extremely accomplished, very smart man who planned meticulously and left nothing to chance. I have done quite a few things in my life, have moved around, seen many different places, have had different careers, but nothing like Mark who was only 36 years old when he died. Looking at his many other interests, I saw that he'd been learning Japanese and wanted to live there someday, was enthusiastic about biodiesel in Australia, Pilates training in Switzerland, all on top of being a certified Cisco engineer.

But there was more. Mark also initiated a discussion forum for English speakers in Switzerland, the englishforum.ch. There was a need for that as Swiss German is as close to a legal secret code as it gets. Mark had commented that while "he was fluent in German, he was completely baffled by Swiss-German and unable to understand even more than a few words." That's because you cannot learn Swiss German. It is only a spoken language. So Mark created a place to help English speakers in the Swiss society. I know the software he used as I use it to run a large forum/community myself. His setup was, of course, completely up-to-date and nicely customized. An "In Memoriam: Mark Fyvie (1972-2008)" was posted on March 13. Within days it had over 300 replies and testimonies to what a great and wonderful person he'd been and how many he had helped. His work had touched people's lives. From all I read about him, I guess he just couldn't help helping others.

Jill Heinerth herself wrote a post and tribute to Mark, her student and friend. She said Mark was a "peer among a very elite group of the world's extremely accomplished and capable technical divers" and that "Mark contributed more to the cave diving community than can ever be measured." In a eulogy on her own website at rebreatherpro.com, Jill wrote "But the reality is that manipulating your own atmosphere for life support is the most dangerous thing you will ever do. Add to that advanced activities like cave diving and exploration and we are on the razor’s edge."

In the end, Mark's time was up, much too soon. In my reading I have often come across divers' frustration when a fatality is simply dismissed as drowning, leaving up to speculation what actually may have happened, and why. Sometimes it's obvious, often it is not. The Megalodon is a rugged, modular and highly regarded electronically-controlled closed circuit rebreather with redundant electronics and a HUD display made by InnerSpace Systems. Mark had indicated he had purchased a radial instead of the standard axial scrubber. The radial scrubber would be able to last as much as ten hours underwater. Inner Space says CisLunar scrubbers also work on the Megalodon and according to an evaluation of the Meg on spiralbound.net, others do as well, though only the CisLunar is mentioned as being radial. Whether or not that made Mark's unit experimental I don't know.

Now one is not supposed to dive solo, though I've read of many wreck divers who feel solo is actually safer under certain conditions where panic can easily result into two fatalities instead of one rescue. As is, my Cavern/Cave Diver Workbook by the National Association for Cave Diving says to "dive with a properly trained and equipped diving partner and maintain diving team continuity throughout the dive." However, that only seems to be a philosophy and not a requirement. As far as safe cave diving goes, "The NACD strongly advocates diving with a partner as the best approach to safe cave diving." Mark had already concluded that finding a suitable buddy for extended time diving was difficult and that he had to do most of his dives alone.

It is equally important to let others know one's dive plan in case something goes wrong. His dive plan was known as he was enthusiastic about his plans and wanted to share with his friends, and at least that aided in the recovery.

The rest is mystery. I'll likely never know what happened, exactly, and it is none of my business. I did not know Mark personally, but his story, so well documented, deeply touched me. May he rest in peace and his loved ones find some sort of solace, nearly impossible though that is.

Posted by conradb212 at 08:23 PM | Comments (0)

March 17, 2008

The Florida Springs

Carol took another flock of her students for certification to Ginnie Springs, Florida, and I was reminded how much I like those springs. And also how peculiar it is that a good deal of my diving experience to-date is in the springs of Florida and not some of the more exotic dive destinations like the Carribbeans. So while she was assessing the skills of her students I began searching the web for more information on the springs, and as usual, one thing led to another and before I knew it I had spent the entire weekend just reading about the various springs.

It's really an amazing thing, those Florida springs. I mean, when it comes to Florida, most people think of sandy beaches, the keys, spring break madness, alligators, swamps, and -- if they are old enough -- perhaps Miami Vice. They'd probably associate Florida with diving, but in the ocean and not inland and certainly not in some of the clearest, freshest water anywhere. But that is what you get in Florida's springs.

How did it all happen in what most people think is just swampland? Well, the northern part of Florida has a vast underground aquifer with several hundred springs. Together they discharge almost ten billion gallons of fresh water a day, with some of the larger ones contributing hundreds of millions of gallons to that total each day. It's all part of a giant storage system. The water originates as rainfall that then penetrates limestone where it is filtered and accumulates in fissures and holes. Combined with carbon dioxide and decaying plant matter, the water becomes mildly acidic and, over many thousands of years, enlarges cracks and holes and creates passages. What it all means is that there is a vast underground system of caverns and caves, many interconnected, in northern Florida and this is the source of all those springs.

The term "springs" is perhaps a bit inadequate because the vast freshwater resources contained in the Floridian limestone system creates all sorts of natural wonders. There are, of course, springs, and they often come right out of the ground. Somehow I associate springs and rivers as something that originates higher up, in the mountains, and then makes its way towards the sea. But Florida's springs come from underground. When you dive, you often see holes at the bottom, with water pushing out of them. Sometimes it's just little boils in the sand. You see them in the clear water, see individual grains of sand twirling around, and feel the flow when you put your hand on them.

But all that water also created grand caverns, nearly endless caves, and also many sinkholes. When we think of sinkholes we generally think of the evening news reporting on a hole in the ground that all of a sudden opened up, collapsing a road or swallowing a home. Those sort of things are usually blamed on human transgressions such as draining or over-using the watertable. However, sinkholes also happen naturally when water slowly eats away at limestone until a ceiling collapses and forms an open entry into the underground spring system.

A good explanation of all this can be found on the "The Journey of Water" webpage of the Florida Department of Environmental Protection.

What does all this mean to divers? It means that Florida has perhaps some of the best diving in the world, and it is in places where you'd never expect it. Instead of sandy beaches, tropical islands, and dive boats, Florida diving seems all shallow rivers and small ponds, some of which covered in duck weed and hard to spot. Once inside, the water is usually crystal clear. That's because it is not stagnant like in a lake, but constantly replaced by the vast volume of water from the underground springs. This phenomenon is exploited by a good number of popular parks and campgrounds located around those springs. People go there to swim and snorkel and just have a good time.

To me, this is what makes Florida's springs so fascinating. There is endless variety. To some people they offer an enjoyable get-away in one of the well-maintained parks with their lush, prehistoric-looking groves and clear, refreshing ponds. Some come to watch the Manatees which like to hang out in the springs. And some dive the caverns and the caves where things can get quite extreme. Manatee Springs state park, for example, both contains a friendly pond and the entrance to a vast underwater caves system that's testing the very limits of courage, skills and endurance in the exploration of many thousands of feet of labyrinthine cave.

During my online explorations I was reminded again of the thin line that separates harmless, enjoyable fun from entry into a deep twilight zone that's as challenging and dangerous as exploring outer space. When Carol and I last dove the Catfish Hotel sink in Manatee Springs state park, I both marveled at the dreamy underwater world that looked like right out of a Pixar movie and shivered knowing that the dark cavern at its bottom was the starting point of Sheck Exley's explorations into the black unknown of endless caves and also where just a few days prior a young man had died when the water had sucked him into the cave.

Ginnie Springs where Carol certified her class likewise has a bright and a dark side. The water in the small spring/pond area is gin-clear, as the location's name implies, but just yards away, underground, lies a massive cave system that has claimed many lives. None other than the great Sheck Exley almost died at Ginnie early in his cave diving career. And, as she later found out, a week before Carol's certification trip, a cave diver had perished deep inside the Ginnie system. Sometimes, a dark side lies just beneath the sunny, friendly surface, and most never even know it's there.

I was reminded yet again of the interesting role Florida's springs play when I found a website dedicated to Florida Springs with almost 50 trip reports and descriptions of springs, rivers and sinkholes in the state's northwest, north and central regions. The site offers an hourlong DVD, entitled "Florida Springs -- The Unexplored Florida" on a good dozen of the more interesting springs. I ordered it and it arrived just a couple of days later. Watching it was an experience. Not only did I see some of the places I had been to myself, but I was reminded again of the secret nature of those treasures. Even the state parks are mostly visited for picnics or swimming and not that many divers know about them.

I also realized once again how diverse the springs are. Some are popular and easily accessible whereas others are virtually unknown or closed off to public access. Some are bright and friendly, others look dark and forbidding. In some you are not allowed to dive at all, in others you pay a fee at the park ranger's office, and some require special permission. According to the DVD, there are even some where you need to check in with the local sheriff and get permission there.

All of this made me want to go back. I'll most likely never dive a cave, will never see what Carol saw, but I may get my cavern certification and poke around some of the better known ones. I cannot wait.

Posted by conradb212 at 04:31 PM | Comments (0)

March 08, 2008

I feel like a total scuba failure

I feel like a total scuba failure. I really do. It's been since last August that I was diving, a couple of pool sessions not included. I really feel awful about that. In a few short months it'll be two years since I got certified and all I have to show for it is about 30 legitimate dives. And this website. How could I create this rather comprehensive website, write the equivalent of a book into this blog, and only have 30 dives to my name? I am not a slacker or procrastinator. How could this happen?

I think of all the excuses I could have for not going diving. I have no dive buddy here. Work doesn't leave me enough time to go diving. Diving trips cost a lot of money. It's cumbersome to get all my dive gear together. There's no place close-by where I can go diving. The small class of people I go certified never stayed in contact. I wasn't ready for a wreck dive in the ocean when my local dive shop invited me to go. I couldn't leave my 11-year-old son on the shore when I was all ready to participate in a salvage operation organized by a local group of divers. And so on, and so on

But those excuses don't really wash. I may not have a regular dive buddy here, but others have overcome this obstacle. I even do the diving website for a local group of divers who regularly invite me to come to their meetings and go on their trips (I never do). My work really isn't a problem. I run a suite of websites and can do most of my work from anywhere as long as I have a computer and internet access. And finding someone to look after my cat really shouldn't keep me from going on a trip. Yes, dive trips can be quite expensive, but it's not that bad. I could afford one or two year. Yes, I don't live by the beach on a tropical island where I can go dive anytime, but Lake Tahoe is closeby and so is the Northern California coast. And if the four people in my dive class didn't respond to my emails, hey, they are not the only people to go dive with. And my gear, well, it's really all neatly packed in my dive bag. It's a lot of stuff, but I do know where it all is, and I keep it all properly maintained.

So it gets back to the same thing: how can I be enthusiastic enough about diving to get certified, do my advanced class, take the Nitrox class, read enough books about diving to -- in theory -- become an expert, do all the research to do this website, and still not go dive on a regular basis?

It's not that I don't want to. I absolutely cherish the memories I have from my few dives. I think of my first night dive and how spooky that was. I think of snorkeling with the Manatees. I think of diving underneath all that duckweed at Catfish Sink to see a magical world and take a picture looking up from the bottom, exactly where the great Sheck Exley once took a picture. I think of testing all those underwater cameras. And I think of locating Rubicon wall in Lake Tahoe and then descend to 110 feet in 48 degree water. I think about the five minutes of fear and uneasiness I always have before I go under (less so in my most recent dives). And I think of the thousands of pages I read about scuba, then summarized in book reports for this website, and how I resolved to experience some of what I read firsthand.

Yet, here I am with my 30 dives. Fact is, I never did actively seek a local dive buddy. Maybe I am the kind of person who needs a kick in the butt to do something. I don't see myself that way, but at least as far as Scuba goes, apparently I am. That bites. I hate it. Sometimes it seems like, for me, diving is like going to a party. I need a major push to go, but once I am there I really enjoy myself and resolve to accept invitations more often.

As is, I have no one to blame but myself for the measly 30 dives in my scuba log.

Posted by conradb212 at 03:36 PM | Comments (0)

February 15, 2008

The submersible Rinspeed sQuba car

Back in 1977, in the James Bond Movie "The Spy Who Loved Me," Roger Moore's agent 007 had a very special Series 1 Lotus Esprit that converted from a sports car to a submarine. The Lotus had propellers and rudders and even a battery of harpoon launchers to help Bond fight off the bad guys. The submarine Lotus was more than just a prop; it did go underwater and the rudder and propellers worked. However, it wasn't actually water-tight, and so a stuntman with Scuba gear operated it inside behind the dark glass. The picture to the right shows a scale model of the submersible Lotus.

Well, now there is a real diving Lotus. Rinspeed, a Swiss tuner and builder of exotic concept cars and other futuristic vehicles built the Rinspeed sQuba, a drivable, divable concept car that really works. Based on a Lotus Elise, the electric-powered sQuba is the brainchild of Rinspeed founder Frank M. Rinderknecht, who never forgot that submersible car from the James Bond movie. “For three decades I have tried to imagine how it might be possible to build a car that can fly under water. Now we have made this dream come true,” Rinderknecht said.

How did they do it? First, there had to be some practical thinking. For example, even though the Lotus Elise is a very small car (only about 150 inches long), the enclosed volume of about 70 cubic feet would have required adding 4,400 pounds of weight. The necessary ballast tanks would have made for a large, bulky vehicle that didn't look anything like a sleek sports car. So Rinspeed decided to build the sQuba as an open vehicle with its passengers using built-in scuba gear while underwater. The car floats on water, then sinks when the doors are opened and water enters the car. However, without passengers it surfaces on its own.

What all did Rinspeed do to make this possible? Well, they removed the combustion engine and replaced it with a variety of electrical motors. For operation on land, the main electric motor makes 73 horsepower and 118 foot-pounds of torque at 4500 rpm. Rinspeed estimates the top speed to be "over 75 mph," but given the weight (less than 2,000 pounds) and power it's probaby over 100 mph. Floating in water, the sQuba uses two propellers in the back, powered by an 800 Watt electric motor each, good for a speed of about four knots. Underwater, propulsion is via two electric 5-horsepower Seabob jet drives that breathe through rotating louvers and expell the water through light but twist-resistant Carbon "nano tubes." That gives the sQuba an underwater speed of about two knots. Power is supplied by rechargeable Lithium Ion batteries. Rinspeed states "the sQuba's filling station is the water reservoir,” referring to the electric hydropower the Swiss are experts in. Operating diving depth is around 33 feet.

When going under, the car's occupants use an integrated air supply system with two gas tanks -- one 15 liters, the other 18 liters -- and Scubapro regulators, specifically Scubapro's classic and very reliable air-balanced G250V second stage. The Scubapro gear and the tanks are mounted behind the passengers.

The sQuba is chuck full of interesting technology, and not only for underwater operation. On land, it uses a laser scanner system to essentially drive itself. For underwater operation, Rinspeed and its partners designed a cockpit and instruments that's inspired by the elegant shape and lines of a Manta Ray. Individual instruments seem to float and have dials that are lined up like lenses. The main control cluster is futuristically lighted and sits behind a protective sheet of glass with a fisheye effect. Controls can be operated even with diving gloves.

How real is the Rinspeed sQuba? Real enough for an impressive video of its operation on land, floating and diving. You can see the movie as well as pictures on Rinspeed's website. It works. But it's also a concept and not meant for production at all. For that, it'd need a more powerful motor, and the market for diving cars is likely very small. But none of that matters. Concepts are limited only by the imagination. "For three decades I have tried to imagine how it might be possible to build a car that can fly under water," said Frank Rinderknecht. "Now we have made this dream come true.” Very cool.

Posted by conradb212 at 12:37 AM | Comments (0)

January 17, 2008

The Dive Computer Blues

January is never a great time for divers unless, of course, you're lucky enough to have booked a dive trip to some sunny paradise, like I promised myself I'd do, but never got around to it. So it's cold outside and the last dive seems ever farther away and you don't know when you get to dive again. That's when you spend time reading dive magazines, go to scuba sites, or catch up on reading dive books. This morning I perused the latest issue of Alert Diver, the bimonhtly publication by DAN, the Divers Avert Network. It's a 64-page saddle-stitched production that makes up in good content what it lacks in commercial design and polish. I like reading it and learn something new every time.

What caught my eye this morning was an article entitled "Deep Calculations, Deep Trouble -- Exploring Safety in Dive Computers." This is a topic I am greatly interested in. I love computers in every shape or form and cannot imagine life without them. But dive computers are somehow different, and I don't feel anywhere near as at home with them as I do with any other computer, and that goes for the ones under the hood of cars and such. I trust my dive computer, and like everyone else, I think dive computers undoubtedly revolutionized diving and made it safer and more convenient. But there are dark sides.

The DAN article, written by Rick Layton, reported on the results of a recent Scuba STAR Network safety survey that investigated how scuba divers use their dive computers, what they know about them, and what experiences they've had with them. The survey didn't have a huge sample, just 42 divers, and may or may not be statistically significant. However, the results are pretty much what I expected, and they are alarming.

The survey said that only 10% of the divers actually learned to use their dive computer with an instructor or in a class. The vast majority simply used the manual that came with the computer, if anything at all. A oood half felt that the training materials were lacking and too complicated or disorganized. The survey also showed that divers are unhappy about the almost total lack of dive computer training in formal scuba classes. They suggested at least a review of all the common features, advantages, disadvantages and problems associated with different types of computers.

An appalling 60% of the respondents reported problems with their dive computer. Many felt screens were unreadable. Others reported blank screens, erroneous data, frozen computers, loss of some functionality, battery problems, and so on. Some computer failed to register depth, failed to display desaturation time, reset themselves, stopped displaying remaining air, or had inadequate rapid ascent warnings. As a result, almost 2/3rd of the respondents said they take along dive tables, and almost a third carries a spare computer.

That is certainly no vote of confidence. And I could definitely relate. Although my own dive computer has worked flawlessly for the year and a half that I have had it, I consider it far from perfect. Its user interface is virtually impossible to figure out. So much so that I have essentially given up trying to understand all the many features it has. I gave the manual several serious tries, but it is so poorly written and organized that I simply cannot figure it out and always give up in frustration. Too bad that there is not a large enough market to warrant a separate "Idiot" book for dive computers. That I understand. But why the manufacturer of my dive computer cannot have a tech writer overhaul their atrocious manual is beyond me. I mean, it could save lives.

The same issue of Alert Diver had another article on dive computers. It was entitled "Living with Dive Computers" and written by Dr. Neal W. Pollock. Dr. Pollock, a research physiologist at the Center for Hyperbaric Medicine and Environmental Physiology at the Duke University Medical Center, listed the various advantages of a dive computer, but also the many things it cannot do, or cannot do yet. However, he starts out saying, "You should know not only which buttons to push to make your computer work, but which mathematical model or model derivation it employs for decompression computation."

I agree, of course, that divers should know which buttons to push, and it's really, really sad that I, who consider myself somewhat of a computer expert, do not know which buttons to push to properly use my dive computer. Heck, I can barely see half the tiny little numbers and symbols on its tiny little low-contrast LCD. But now I am even supposed to know which mathematical model it employs for decompression calculations and, presumably, what that means to me?? Though I have a doctoral degree myself, and in a technical discipline, I don't think that expectation is remotely realistic. And if it isn't for someone like me who always wants to know how things work, I think there are others who may struggle with the concept.

But let's say it'd indeed be prudent to a) learn what buttons to push, and b) know the mathematical models that are used in dive computers. What would that mean? I'd say even the former is nearly impossible. Virtually every dive computer is different. I've seen more than one Scuba instructor unable to explain the operation of a student's Dive computer, and those were good instructors. Dive computers do not have a common interface, like Microsoft Windows or the Mac OS, or eve common controls, like computers have a mouse or a touchpad. So instructors may begin spending as much on dive computer basics as they do on dive tables.

Then they may have to get into the difference between table-based computers and model-based computers. Table-based is simple; the computer just uses the dive tables and quickly calculates all you need to know. But most dive computers are model-based, i.e. they make all sorts of assumptions. The oldest and most traditional model uses the Haldane models, named after the Scottish scientist who developed the theories and tables for the British Royal Navy. Haldane tables and concepts still form the basis for most die tables and dive computers, but there are many others as well.

What this means is that a diver would have to know not only about the Haldane theories, but also about statistical models, variable permeability models, reduced gradiant bubble models, slab models, Series models, and EL (exponential/linear) models. Add to that the various proprietary models, hybrids and assorted secret sauces manufacturers use in their computers, and the likelihood that many divers know what mathematical model their dive computer uses and what that entails is essentially nil.

Can we hope for standardization? Probably not. Will there be ongoing research that in conjunction with advancing technology will result in ever more sophisticated dive computers? Definitely.

Posted by conradb212 at 10:47 PM | Comments (0)

November 28, 2007

Pony bottles -- a good thing to have, or not?

To keep in shape I am going for a run every other morning. Religiously. I've been doing this for about five years now, without fail. I missed perhaps half a dozen runs in all of those years, and that's when I literally could not make it out of bed because of the flu or some other nastie. My run is only a couple of miles or so, but it's uphill and downhill and thus gives me a good workout. My heart and breathing rate go way up and every run hurts. No pain, no gain, I suppose. It's never easy and it never gets any easier, or at least it didn't after the first couple of weeks or so when I first took it up.

One thing I am always aware of when I run is air. Early on I determined that I was going to breathe through my nose the first part of the course and until it gets really steep. Then I remove that restriction and gulp in as much as I can. Ever since I took up scuba, I've been looking at breathing differently. I now know more about how our bodies use oxygen, why we have the urge to breathe, and the whole complex mechanism. When I run uphill -- "run" is perhaps an exaggeration; "slowly jog" is more like it -- I breathe so hard that it just doesn't seem possible that my muscles need that much oxygen, yet the urge is there. And I know that should my air be cut off, I'd instantly ... what? Die? Collapse? Pass out? I don't know, but it's hard to imagine not having air. Fortunately, that's just not an issue when you go running.

Underwater it is. No air, you're dead. That's why sharing air with your buddy is one of the first things you learn in Scuba class. Do not panic. Calmly signal your buddy, then assume the position and use the buddy's backup octopus second stage. Or you may have agreed that the buddy will use his or her integrated backup second stage, like the Scubapro AIR2 I have on my Knighthawk BC, and let the buddy use the primary that has a longer hose. If worse comes to worse and there is no secondary, you do buddy breathing where you share a single second stage on the way up. In theory those are good solutions, but I've always wondered what it might look like if you're at 80 feet with low visibility, your buddy has temporarily gone out of sight, and that is when something goes wrong with the air.

Now I know that by and large, scuba gear is extremely reliable. Things are not likely to go wrong, but there really is always something that can go wrong. Stuff can jam, break, rip, get lost, fall off, or you simply run out of air. And when you're down there, that's deadly. I've read a fair bit about cave diving, something that I'll likely never do myself but that fascinates me, and the first rule there is that everything must be redundant. Every system has a backup, and usually even the backup has a backup. That makes sense. Pretty much everything we use in life has a backup if it is really important. The brakes in a car, for example, have multiple backups.

So why does standard scuba equipment not have a backup for air? Everyone except tech and speciality divers just dives with a single tank, and should something go wrong, it's quickly finding the buddy and sharing. To my way of thinking, that's simply not a very good solution. Especially since there are ways to have backup. They are usually called "pony bottles."

Pony bottles are small air tanks with a separate regulator meant to be used in emergencies. Which makes a lot of sense to me. But from what I can tell, few people use them, and there is an amazing amount of controversy over them. Much more than I'd expect over something that seems to so sensible and logical. The primary bone of contention seems to be size.

One company that specializes in backup air is appropriately named "Spare Air." Their standard model has 3 cubic foot of air, a bit bigger than their original bottle that had just 1.7 cubic foot. The company claims that over a hundred thousand of those little mini tanks are in use. The bright yellow spare air bottles are packaged in neat systems that include mounting gear, an integrated regulator that sits on top of the bottle and does not use a hose, and a carry bag. Problem #1 is that they are not inexpensive. They cost around US$300 which is a bunch more than most big 80 cubic foot tanks. Problem #2 is that neither 1.7 nor 3.0 cubic feet of air gets you very far. The company estimates 30 and 57 breaths, based on 1.6 liters per breath. That's on the surface. Which means it's half that at only 33 feet, and a third at 66 feet. If things go bad at 66 feet, ten breaths won't help all that much, and neither does 19. And even that's assuming that you gulp in just the estimated 1.6 liters, and not a lot more as people tend to do when things go bad. Oh, and they are usually filled by connecting them to your main tank. So if you have a low pressure tank like my big old Steel 95s, then you'll get less air in the baby tanks yet as filling them to capacity assumes you start with 3000 psi.

So what about larger bottles? Pony bottles are made by many manufacturers, and they generally come in sizes between six and 40 cubic feet. They cost less, mostly because they don't come with a regulator, so you have to get one. With these pony bottles it's actually possible to bring along a fair-sized backup, enough to bail you out. But now it becomes a question of balancing the amount of backup air with the inconvenience of shlepping along a sizable second tank that needs to be mounted somewhere. A little 3 cubic foot Spare Air clips on just about anywhere on your gear. A 20 or 30 cubic foot tank, that's already another story.

Those firmly opposed to pony bottles say just that: if it's small enough to not be a bother, it's useless because it does not have enough air to be of any practical use. It simply lulls its user into a false sense of security. If it is large enough to have enough air for a serious emergency, then it is also large enough to slow you down, increase the chance of getting entangled, and just generally is a bother to lug around. So either way, they're no good and relying on your buddy makes much more sense.

Does it? I don't know. I've never been in an iffy situation, and I hope I never will. I do know that the thought of having my own backup sounds comforting. The motto of the Spare Air folks is "Because Self-Rescue is the Ultimate Buddy!" and that makes a good deal of sense. I wonder how the majority of divers feel. I rarely see anyone with a pony bottle, so perhaps most do indeed rely on their equipment and their buddies. Fortunately, I know I can rely on mine, always.

Posted by conradb212 at 04:01 PM | Comments (0)

November 22, 2007

Oceanic Datamask: MUST - HAVE - IT - NOW!

A couple of weeks ago I received an email invitation to the Grand Opening of a new dive shop, Fish Eye Scuba, in my town. Timing was bad as I had planned on going racing that afternoon and evening and so I thought I'd probably stop by the new shop some other time. Well, on my way to the track, the car wasn't running right and I decided it'd be too risky to push things at the race track. As luck would have it, the new dive shop was on my way home, and so I went to check it out.

I love dive shops as much as book stores and maybe more. Whenever I go to one, I never spend less than an hour or two perusing all the gear, asking a bunch of questions, compare notes and all the fun stuff we do in dive shops. And I almost always end up buying something that I may or may not need, but that I absolutely have to have.

I was early and they were still gearing up for the Grand Opening. So they set up all the food and drink, and a disc jockey prepped his gear. I got a chance to meet the owners, chat a bit and then look around while the place wasn't totally crowded yet. It wasn't a large store, but it was neatly laid out and decorated, had lots of interesting gear, and some of the high tech touches I am a sucker for. A huge flatscreen ran underwater footage in glorious high definition.

So I grabbed a sandwich and a bottle of water and checked out the gear. They are not a Scubapro dealer, unfortunately, and 90% of my gear is Scubapro, but I love to look at and try out new stuff. By now people were trundling in, greeting and hugging each other and soon the place was packed.

That's when I saw it. In a locked glass case.

It was the Oceanic Datamask, a combination of mask and dive computer. My Open Water class instructor, Chuck Odell, had mentioned it to me early on. As a former Navy SEAL he was close to such things and I think he may have mentioned that he'd get one of the first ones. That's because the Datamask began life as a joint development project between Oceanic and the US Navy's Coastal Systems Station. Its original name was the "Combat Diver Display Mask". The idea was to combine mask and computer, have an optical readout right in the field of vision of the diver, thus reducing the need to interrupt operations to look at a wrist-mounted dive computer. One might argue how important that is in the larger scheme of things, but it is certainly high-tech and a fascinating idea.

So they did it, and the civilian result of it is the Oceanic Datamask HUD, with HUD standing for Heads Up Display. It's been available from Oceanic since early 2007 or so, and the company has been demonstrating it at dive shops and scuba get-togethers. I had never seen it in person, but now here it was, in that glass cage.

One of the Fish Eye Scuba sales staff was kind enough to open the case for me and a couple of other interested parties and so we got to check out the Datamask. At first sight it looks like a regular single-lens black rubber/silicone mask, but then you discover that there's more to it. There are some protrusions on the right side, and the lens is asymmetrical, with the right side of the glass area being smaller than the left. That's to make room for the electronics and also the integrated LCD screen. Doesn't that make the mask heavy and bulky? Amazingly not. The mask really feels like any other mask, it has fairly low volume (which I like), and it has excellent fit, with a well designed skirt.

I should mention here that the Datamask is both air-integrated and wireless. It comes with a wireless receiver that screws into the regulator's first stage. If you wear both the Datamask and a conventional wireless dive computer as a backup, the signals won't cross as they operate on different frequencies.

So how does it all work? Well, it's simply a case of the functions of a modern dive computer being built into the mask. If you look straight ahead, you have the same unimpeded field of vision as with any other mask. If you want to see the computer, you look down to the lower right. This is where the LCD screen sits, but you don't really see it as an LCD screen. It feels more like the data is floating ahead of you in space, or rather in the water.

How do you operate it and what can it do? Here, the Datamask's designers came up with an ultra simple method that uses just two buttons, one on top of the mask and one on the side. Each button has two functions: push and release, and push and hold. Those two buttons control all of the functions and display modes of the Datamask. Like all dive computers, after initial setup it'll simply work if you put the mask on and go dive, but if you want to really use its features, there'll be a bit of studying and practicing. And maybe quite a bit. The Datamask (which is Nitrox compatible up to 50%) has a significant number of screens both for setup on the surface and then for diving. It has automatic altitude adjustment, the main battery in the mask lasts about 160 dive hours and the one in the transmitter 1500 hours, it can store 24 dives and comes with a USB interface cable and software for data analysis on a PC. Setup lets you select alarms, units, sampling frequency, lighting, a concervative factor, and tons more.

When you dive with the Datamask, there's a main screen that displays the usual primary data: depth, air pressure, remaining dive time, air time and a tissue loading bar. Push a button and the display goes on to three additional screens with more data. Those then revert to the main screen. There are also screens for safety stops and deco stops.

Now obviously, I have not (yet) been diving with an Oceanic Datamask and so cannot say how it all works in real life. I do know one thing, and that is huge for me. While I have 20/20 vision I do need reading glasses, and that is forever a pain with wrist-mount dive computers. I tried stick-on lenses that either seem to be in the wrong spot (often due to the design of the mask lens) or come off (at times because manufacturers edge writing on the inside of the mask exactly where the stick-ons are supposed to be). No good. I tried masks with magnification windows pointing down, and found that distracting. Amazingly, I can see the HUD display of the Datamask clearly and in perfect focus! That alone would make me want one!

How DOES it work in real life? Well, I searched the web for reviews and found surprisingly little. A couple of people had used it during one of Oceanic's demo tours and written about it. There was one single actual review of the Datamask. It was fairly brief. The reviewer found the mask amazingly easy to use, felt that the LCD display was unexpectedly basic and at times difficult to read, that pushing buttons on the mask was a bit weird at first, that having one's computer inside a mask made it impossible to show it to the dive buddy, and that a backup was a good idea in case the mask comes off. And he wondered how it works with thick gloves on. All in all, he liked it. On various scuba bulletin boards others had issued various sight-unseen opinions: Too expensive. Can't do this, can't do that. I'll wait until they come down in price.

So what's the price? Well, currently US$1,495. That's one expensive mask, of course, but then again, no more expensive than my own UWATEC dive computer and Scubapro Frameless mask combined. So there.

The guys at the dive shop offered me a deal and I came THAT close to whipping out my VISA card right then and there. I really want that mask. I wish Oceanic would let me test one. Hey, after all I have written over a thousand published reviews of electronic gear. But the scuba industry seems stingy with eval units and so I may have to buy the Datamask after all.

Posted by conradb212 at 06:23 PM | Comments (0)

November 09, 2007

Nitrogen Narcosis

I've been thinking more about nitrogen narcosis, the threat to divers when they dive too deep. Given that humanity knows so much about just about everything, from putting hundreds of millions of transistors onto microchips the size of a fingernail, to decoding the human DNA, to building giant bridges and tunnels to running remote-controlled vehicles on the planet Mars, it's amazing how little we know about nitrogen narcosis. Almost every dive book mentions it, yet there seems little agreement on it other than that it can be dangerous and divers are susceptible to it and react to it in different ways.

The most common explanation is that as we go deeper, the higher partial pressure of nitrogen has some sort of impact on our consciousness. It's conjectured that perhaps at these higher pressures nitrogen dissolves into nerve membranes and thus causes them to function differently, perhaps affecting the way signals travel inside our brain. Some view that as a cool thing. Jacques Cousteau called it "rapture of the deep," which has a nice ring to it and doesn't exactly sound dangerous. Others have mentioned looking forward to some pleasant buzz. But even Cousteau, of course, knew it could be dangerous.

Almost everyone agrees that nitrogen narcosis can lead to unanticipated feelings and thus behaviors, and that is not a good thing when you have a hundred feet of water above you and your well-being and survival depends on logical thinking and remembering what you have learned. But how can you deal with something when you don't know what to expect, when to expect it or what it'll make you do, if anything at all?

I am an avid reader, and for the past year or two it's been mostly dive books. Nitrogen narcosis is mentioned in almost every one of them. In older books, or when quoting older passages, nitrogen narcosis is often likened to having a dry martini (consisting of mostly gin (or sometimes vodka) and a bit of dry vermouth) for every 50 feet of depth. So if you're at 100 feet, that's supposed to be like downing two dry martinis, and 150 feet three of them. That is a lot of booze on an empty stomach, and poured down the hatch. Others use the "martini law" with different rules, like narcosis effect being like one additional martini for every 33 feet, starting when you reach 66 feet. Some writers describe the martini comparison as politically incorrect.

My friend Dave, a former diver who let his skills lapse and hasn't gone diving in many years, remembers his experience with narcosis. He said he was diving off the coast of some nice, sunny, friendly place when suddenly everything seemed to look really cool and colorful and he saw some irresistibly interesting things down deeper. So deeper he went to check it all out. Next thing he knew his dive buddy had grabbed him and brought him back up to the 70 feet or so where his narcosis had set in. So for him it definitely had been "rapture of the deep," even if it wasn't particularly deep.

One area where most experts and accounts appear to agree is that unlike alcohol induced impairment, you can get rid of narcosis simply by ascending. So the assumption is that the impact of nitrogen narcosis is directly proportional to water pressure, or depth. So if you have the experience and presence of mind (or the luck) to be able to recognize and control narcosis, you simply ascend a bit if the impact of narcosis becomes too much. However, there are dissenting opinions. At least a couple of authors stated that, no, the impact of narcosis lingers, just as does the impact of alcohol. Perhaps not for as long, but it definitely won't just vanish if you ascend.

Everyone seems to agree that nitrogen narcosis is hard to pin down as it affects different people in different ways, that it can manifest itself in different ways, and that its onset is unpredictable even within the same individual under similar diving conditions. Not even the depth at which nitrogen narcosis begins to show itself is a given. Some are affected at fairly shallow depths whereas the onset occurs much deeper for others, and some seem almost immune (or at least able to control it effectively).

The symptoms described in literature vary to a great extent. Narcosis may cause pleasant feelings such as exhilaration, happiness, thrill, giddiness, or negative ones like anxiety, depression, or general gloom. As a result, judgment becomes impaired, vision may become impaired, and things can go bad. Most texts state that nitrogen narcosis affects all divers, that its effects are rarely noticeable at depths of less than 60 feet, that serious impairment happens at around 100 feet, and extreme depths of 300 feet or so on air result in narcosis induced halucinations and loss of consciousness (using the various "martini" rules, that'd be six to eight of them; I'd definitely be unconscious!)

Almost every dive book describes examples of narcosis, and, as expected, they vary greatly. In one book, an experienced wreck diver was said to become "addled" and essentially unable to think and function at just 85 feet. In other accounts, deep dives to well over 200 feet on air describe narcosis as just a minor nuisance. Everyone agrees that environmental conditions have a big impact on narcosis. If it is cold and dark, it seems to affect people worse. Then again, it hit my friend Dave at just 70 feet in friendly, optimal conditions.

These days technical divers use special breathing gas mixes to reduce the impact of nitrogen narcosis. For relatively shallow dives Nitrox, the breathing gas with more oxygen and less nitrogen, reduces the risk of narcosis, though it is primarily used to extend bottom time due to less nitrogen being absorbed into the diver's body. Nitrox is unsuitable for deeper dives because then the oxygen becomes the limiting factor as high partial oxygen pressures result in seizures. The answer is Trimix where oxygen, nitrogen and helium are mixed for optimal results (or least potential for damage) at deeper depths. A certain Trimix concoction may contain the proper percentage of oxygen to give the diver enough to sustain life but not so much as to cause seizures; a percentage of nitrogen that will result in enough bottom time for a given depth without the penalty of excessive decompression stops; and the rest in helium, a costly gas that has its own issues, some of them poorly understood and hotly debated.

There are examples of deep divers who used air and simply learned to cope with the impairment, others who switched to Trimix and praised the sudden clarity of thought they had during their deep dives where they'd become used to having to muddle through, and yet others who paid dearly for avoiding the cost of Trimix gasses in favor of plain compressed air.

So how does nitrogen narcosis affect me? Up to recently I simply did not know as my deepest dives had taken me only down to just under 70 feet. My high altitude dives in Lake Tahoe were different. The visibility was good, but several other factors might well have affected the onset of narcosis. I had never gone nearly that deep. The water was cold, down to 48 degrees. And then there was the impact of high altitude diving where equivalent depth is even deeper than actual depth.

So did it affect me? Well, on the first dive I felt a bit uneasy because it had been several months since I'd been diving and because, following my dive buddy Carol, I quickly found myself deeper than I had ever been before. We stopped around 80 feet or so and I felt uneasy. I looked up, knew I had 80 feet of water on top of me, and suddenly felt a slight onset of panic, the kind where you feel not quite right. When that happens on land, you may lay down or drink a glass of water or whatever. At 80 feet that isn't possible, but I knew I did not want to stop and needed to keep moving to keep the uneasy feeling from grabbing a hold of me. So I slowly swam around Carol, and the feeling passed. When she gave me the Ok? sign, I answered back. Ok. And followed her deeper. I had never expected the dive to be so deep and so impressive, but it was. Carol showed me the depth reading on her dive computer every ten feet and stopped to take pictures of it with her underwater camera. I'd taken mine along as well, the Olympus 770SW.

We were now pretty deep and Carol, who was a few feet below me, motioned for me to come down to her. I checked my dive computer and saw 94 feet. She had wanted me to experience 100, but for now 94 felt enough to me. I did not feel compromised or disoriented or buzzed in any way. On the way down to 94 feet I did realize that I had probably flooded the camera. The 770SW has a depth rating of 33 feet without deepwater housing, and I'd taken it down to 67 and Carol to 77. So it was not that I had simply forgotten about the camera; I simply expected it to continue to work. I did not write that off to narcosis, as in I'd completely forgotten that I had the camera with me. I hadn't.

The second Lake Tahoe dive was the Rubicon wall dive. Here we knew we were probably going to go deep, just not how deep. We didn't even know at what depth the wall started. This time we used hoods and gloves so that we'd be less affected by the cold. Despite the unfortunate flooding episode, this time I took two cameras along, both Sealife Reefmasters. We found the wall at 70 to 80 feet. I'd wondered how I'd feel one I came face to face with the wall, where there suddenly would no longer be a bottom. Once I got there, I felt neither elation nor uneasiness, but simply followed Carol over the wall and down. It quickly got much colder, and Carol, who wore only a 4mm wetsuit stopped at 100 feet. I wore my hefty 7mm suit and felt fine. To the best of my recall, I still felt neither anxiety, giddiness or anything else unusual. I just felt good and in awe of everything I saw, as I always do on dives.

I was proud that I had finally reached 100 feet, but all seemed so well that I decided I wanted to push a little farther. So I motioned to Carol that I intended to go down to 110 feet. I didn't use the proper hand signals. Instead, I pointed at my depth reading, then signaled a number as I would on land. I pointed down, then showed five fingers, five fingers again and then one, for 11, or 110 feet. Then I slowly descended, watching my depth gauge. Once I reached 110, I was satisfied (well, very pleased is more like it), and ascended again to 100 feet where Carol hung. By now she was very cold and we began our ascent.

Had I experienced nitrogen narcosis? Was narcosis what made me feel uneasy for a minute or two on the first dive and also flood my camera, and then brave enough to descend another ten feet once I had reached the magic 100 mark on the second? I don't know. I don't think so as I never felt compromised and never did anything that either Carol or I felt was irrational or out of control.

So I don't know. Maybe I am one of the lucky ones who have a fairly high tolerance for nitrogen narcosis. Maybe it just didn't happen on those two first deep dives. Maybe it did happen and I just didn't notice. I don't know. Most likely I'll eventually find out.

Posted by conradb212 at 11:21 PM | Comments (0)

October 10, 2007

Watching "The Deep" again

Last night I watched "The Deep" again. Given the significant popularity of the sport, there are not a lot of diving movies, just as there are not a lot of diving books. Sure, there may be the occasional diving scene in an action flick, but movies where scuba takes center stage are few and far between. And some of those where diving does play a prominent role are not exactly academy award material.

I remembered "The Deep" as a pretty decent movie, though I hadn't seen it in 20 years or so. The novel and screenplay were done by Peter Benchley, who also had his hands in any number of creature movies, including Jaws. Peter Yates was the director, also a man with considerably experience. His movie "Bullitt" with Steve McQueen remains an all-time classic. And, of course, the stars of "The Deep" had considerable drawing power: Nick Nolte, Jacqueline Bisset, Louis Gossett Jr., and actor/writer Robert Shaw who had some 50 movies to his name (including Jaws and a couple of James Bonds) and died shortly after "The Deep" was released in 1977.

So this was diving 1977, and that alone was enough to make me want to see "The Deep" again. But there was another reason. Diving legend Stan Waterman had worked on the underwater scenes of the movie, as both a director and a cameraman. I have met Waterman, a diving legend and now in his 80s, personally and enjoyed one of his eminently entertaining and educational lectures.

The movie is about a young couple vacationing and diving in Bermuda. They dive a WW II wreck and come across a large stash of morphine ampulles, worth a fortune on the drug market. Word gets around, and the bad guys, led by Louis Gossett Jr. are soon on their trail. But there's more. Seems that storms sort of mashed that WW II warship and a much older vessel together, and so there is treasure. Treasure is good, but it's really worth a whole lot more if its authenticity can be established, and so the stage is set. Bad guys after drugs. Good guys doing research on the suspected treasure. Throw in some ghastly VooDoo, motorcycle chase scenes to liven up the somewhat twisted plot, and then there's the diving, lots of it. That's what primarily interested me.

This is 1977, really not that much past all the Cousteau documentaries I'd watched. Yet, whereas Cousteau's footage always had sort of a Buck Rogers back-to-the-future look to it, what with their sleek, futuristic, aerodynamic gear and their double hose regulators, diving in "The Deep" looks surprisingly modern. It must be warm as Nolte and Bisset only wear bathing suits. In Bisset's case, a rather revealing skin-tight T-shirt with prominent nippleage was probably sensuous enough to send censor types into shock. Other than that, modern-looking regulators, modern looking masks, single tanks, nothing that would look out of the ordinary today. Except for one thing: no BCs. In 1977, buoyancy compensators did exist. Scubapro developed the stabilizer jacket in 1971, and so called adjustable buoyancy life jackets had been around since 1961. So I don't know if by 1977, it still wasn't common to use BCs.

The dive masks they used looked like something you'd buy today. Light and clear and low volume. The underwater photography was terrific in every respect. As is usually the case in movies, some things made me wonder. Like, they penetrate this wreck they do not know without protective gear or lines at all. More interestingly, silting never seems an issue. They swim around, push, pull, fight, yet hardly any silting at all. Visibility is always a-okay. The shipwreck used in the movie was supposedly that of the RMS Rhone that sank in 1867, with filming taking place at 75 feet in the bow section. Much of the diving actually looks much shallower than that, which makes me wonder how the picked the title "The Deep." Oh, and this was before dive computers. Still, no one ever runs out of air, and I don't think I saw a single decompression stop or anything like that.

There was some excellent shark footage. The bad guys threw fish and bait into the sea to attract sharks, and the resulting footage is awesome, especially for the time. I could just picture Stan Waterman, that pioneering shark cinematographer, behind the camera, not quite knowing what to expect. Another bad guy critter is a truly giant moray eel in the wreck. Morays always look evil. This one actually ends up crunching Lou Gossett Jr.'s head and biting it off. Ouch.

All in all, it was nice watching "The Deep" again. It is not a very good movie, especially given its illustrious cast, but the dives scenes were great. And Jacqueline Bisset sure looked good underwater. Maybe that's why they didn't wear bulky BCs.

Posted by conradb212 at 11:21 PM | Comments (0)

October 03, 2007

Less dive time for NAUI divers?

Two friends, a NAUI diver and a PADI diver, decide to go on a dive trip. Though they have dive computers, they decide to play it by the book and use dive tables. They also decide to take it easy and do just two dives each day, though some are fairly deep. They know the dive sites, decide on surface intervals between each day's dives and begin working out their dive plans. When they are done, they compare their plans and find something very peculiar. For their second dives of each day, the PADI diver shows a total permissible dive time of 443 minutes whereas the NAUI diver arrived at only 301 minutes. They recheck their calculations. They are correct, yet for each dive except one, the PADI diver finds longer allowable dive times for the second dive, sometimes by a lot. For example, after a 60 foot dive and one hour surface interval, the PADI diver can do a 61 minute dive to 50 feet. The NAUI diver can stay only 42 minutes. After a 40 minute dive to 70 feet, the NAUI diver can hang around at 40 feet for 69 minutes, whereas the PADI diver can stay for 115 minutes (if he has that much air). After a deep dive to 133 feet, the PADI diver can, after three hours on the surface, make another deep one to 90 feet for 21 minutes whereas the NAUI diver has only 18 minutes.

What gives? Aren't all those dive tables based on the same principles? Should they not yield approximately the same results? True, the PADI and NAUI tables are different, with PADI breaking things down into 26 "Pressure Groups" while NAUI has less granularity with just 12 "End-of-Dive Letter Groups." So you'd expect the tables to occasionally produce slightly different results, but not by much. Sometimes PADI would show more bottom time and sometimes NAUI. But that does not appear to be the case. The NAUI tables seem to consistently yield more residual nitrogen time and less maximum dive time for repetitive dives.

Does that mean NAUI is more conservative? I don't know the answer just yet. Based on my own experience, I've come to view PADI as more tourist and recreation oriented, and NAUI as more technical and detailed. If that were indeed so, then one would expect PADI to be more conservative so that its broader and perhaps less experienced diver base stays within safe limits at all times. Instead, the respective dive tables almost always allow less repetitive dive bottom time to the assumedly more experienced average NAUI diver.

Could definitions have something to do with it? Just like the PADI and NAUI dive tables are different, so are the two competing certification entities' terminologies and definitions. As a result, as if dive tables weren't confusing enough, those trained by different agencies must also figure out if "Actual Bottom Time" is the same as "Adjusted Maximum Dive TIme," and "Total Bottom Time" the same as "Total Nitrogen Time." That's just not good.

Looking at my notes and instruction materials, I find that NAUI defines "actual dive time" as "the time from the moment of descent until returning to the surface." Breaking the surface or starting to return to the surface? For PADI, on the other hand, "bottom time" is "the total time in minutes from the beginning of descent until the beginning of final ascent to the surface." So the NAUI "total nitrogen time" which adds "actual dive time" and "residual nitrogen time" would yield a larger number than PADI's "total bottom time" that adds "actual bottom time" (which does not include the time it takes to ascend) and "residual nitrogen time." Confusing for sure.

And there's another difference. PADI states that "if you don't plan to dive for at least six hours, the residual nitrogen has little consequence. True enough, if you look at the PADI Recreational Dive Planner, you find that after a six hour surface interval you are no longer in any pressure group at all and a second dive, even if the same day, would apparently not be treated as a repetitive dive. NAUI, on the other hand, categorically states that "any dive made less than 24 hours after a previous dive" is a repetitive dive. Which means that no matter how long the surface interval on any given day, for the second dive you'll always start out at least in End-of-Dive Letter Group A.

What does it all mean? Nothing for most divers because very few will ever agonize whether to use the PADI or the NAUI dive tables. And most divers simply rely on their dive computers anyway. But those large discrepancies between the tables are still amazing after being taught in class that even a couple of minutes of extra bottom time can be the difference between a safe dive and the prospect of getting bent.

Posted by conradb212 at 11:20 PM | Comments (0)

September 17, 2007

Taking a handheld computer underwater

When I took that advanced NAUI class I was exposed to all sorts of disciplines. Night diving, light salvage, advanced buoyancy, navigation, deep diving, rescue, using scooters -- all were part of the training. On my own I also picked up the basics of underwater photography, learned how to go about high altitude diving and now have taken the Nitrox class. But I learned even more, and that is how to integrate scuba diving into my work, which is reviewing and writing about all sorts of gadgets and technology, from digital cameras to handheld computers to those ultra-rugged notebooks that the military or firefighters use.

How would diving come in handy for that? Well, with cameras it is obvious. There are many of them that you can take underwater. Most with housings, and now more and more that don't even need one as long as you don't go deep. So knowing camera technology and being a diver lets me take my reviews underwater, and that opened a whole new area for me, one that I greatly enjoy.

But computers? I am not talking dive computers here, the ones we take down to great depths, but just regular computers. So what's this all about? Well, manufacturers realize that not all PDAs and notebook computers will lead a sheltered life sitting on desktops and meeting room tables. Some are used outdoors, some are dropped, some are rained on, and some may even get banged around or crushed. The military, for example, needs the equivalent of a HumVee in a computer, and not some plasticky thing. Anyone who uses a computer as a tool for a job needs just that, a tool, and not a gleaming conversation piece with a panorama screen so that DVDs can be watched on it.

Which means that there is a significant industry out there that makes nothing but tough, rugged computers for special purposes. Panasonic for example, they are a household name with their TVs and electronics, but they also make the "Toughbook" line of notebooks that can take much more punishment than a standard laptop. Companies like UPS or FedEx buy hundreds of thousands of handheld computers they use on the job, to scan and track packages and capture signatures. Those handhelds must be pretty tough to survive all that, day after day and month after month.

There are some standards the industry uses to describe how rugged a computer is. Most come from the military and simply describe testing procedures. The MIL-STD (military standard) alone consists of hundreds of pages of how it's all done. Most countries have their own, and then there are some industry associations and institutes that also have standards, so it can get a bit confusing. Reading and deciphering those ruggedness specifications, and then figuring out what it means in real life, is part of my job. The one standard I think matters more than most is the IP rating. That stands for "Ingress Protection" and was defined by the International Electrotechnical Commission. A mobile computer's IP Rating is expressed as a two-digit number, like IP-56. The first number designates protection from solids (from 0 to 6), while the second number designates protection from liquids (from 0 to 8).

All dive computers would have an IP68 rating if they were tested for that. IP68 means they are completely protected from dust getting inside, and, of course, they are completely waterproof and protected from the effects of immersion. Regular computers are not. They don't have to be. But maybe they should, at least to a degree.

To make a long story shorter, there are some handheld computers with an IP67 rating, which means they can actually be immersed into water and survive. It's just baby steps for now, with immersion usually limited to about a meter and for no longer than 30 minutes or so. And even that is extremely rare. It so happens that I got one of those computers to review and test, a very tough handheld from a company called Tripod Data Systems. Their new Nomad computer is for the military, for surveyors, and others that need to computer and communicate in extreme conditions. It's a very sophisticated unit with a fast processor and a razor-sharp display that puts the Apple iPhone to shame. And it's rated IP67, with 30 minute immersion to a meter of water.

Needless to say, I had to check that out for myself. My regulator and BC had just come back from their first annual service and I was absolutely dying to get back underwater. If I had a dive buddy, I'd have gone up to Lake Tahoe to catch another dive or two before the water gets too cold up there. But I could not find one, and so it had to be my pool.

Preparing for the dive with the Trimble Nomad computer required some planning. First was the mental step in deciding to actually do it -- take an expensive piece of equipment underwater, one that I needed to send back to the manufacturer. What if it flooded? The second was to record the event, and for that I needed cameras. I decided to use a Casio Exilim EX-Z77, also here for review, for the above-water scenes as it includes a cool new "YouTube mode" which means it spits out video optimized for the YouTube video sharing service. For underwater I picked a SeaLife DC600, mounted on a regular tripod. My eleven-year-old son Morgan was my assistant and he certainly earned his pay (in chocolate-covered peanut pretzels).

So I am finally all geared up and wearing my new "Edge" 3-mil wetsuit. I do some preliminary tests by carefully immersing the computer into the water and watch for bubbles. On camera. No bubbles. Now Morgan joins me in the water with his snorkel gear. He holds the only slightly negatively buoyant tripod with the SeaLife camera on it steady and starts recording. I am going down, making sure not to descend deeper than three or four feet, holding the Nomad computer in my hand. I circle the pool, then stop in front of the camera and operate the computer with its stylus. The touch screen operates just fine. I bring up some menus, click here and there - no problem at all. The Nomad, like many handheld computers, has handwriting recognition, and so we try to capture that in a closeup. It works, but the screen is too reflective to get a good shot with the camera, and so that didn't quite pan out. I do a final underwater lap around the pool and surface, with Morgan capturing that on the Casio.

So that was diving with a handheld computer that was probably never meant to be used in scuba gear. But it could handle it, and now I wonder if perhaps we won't be seeing underwater computers sometime soon. They'd sure beat a white slate and a pencil. Perhaps. There are times when throwing expensive technology at a simple problem makes no sense, but I'd like to see it anyway. Imagine drawing, reading an eBook, emailing or testing, or even browsing the web during a long, boring deco stop. Or using the dive slate's built-in digital camera. The opportunities are endless.

As is, I got to dive again, and I got to do something new and exciting. I needed that. An event that I had looked forward to all year was recently cancelled. It was to be my first dive trip to a "real" exotic dive location. I had practically lived for that all this year, thought about it while falling asleep and dreamed how great it'd be, but due to circumstances beyond my control, it won't happen. So that totally threw me for a loop and left profound sadness that I have been unable to shake. I think diving and all that it means and includes is more than just a sport. I am not quite sure what it is, but I know it changed my life.

Posted by conradb212 at 11:20 PM | Comments (0)

September 14, 2007

Nitrox certified

I was certified for Nitrox use on September 12, 2007 after completing the PADI course. Why PADI and not NAUI? Primarily because preparation includes a lot of work with dive tables, and once you become used to either the PADI or the NAUI method, it's difficult to change. The tables are, of course, based on the same principles, but just different enough to thoroughly confuse you. So I figured why add confusion to an already confusing thing like using dive tables?

It's interesting how those courses are conducted. You actually do all the studying beforehand with the coursebook in the crew pack. You also watch the DVD that covers the exact same material, but makes it all look nice and friendly. And you practice with the included dive tables. For the Nitrox class that's plastic dive tables for Nitrox with 32 and 36% of oxygen, and a table that shows equivalent air depth for mixtures with 30 to 40 percent oxygen. On the other side of that one is an Oxygen Partial Pressure table you use to calculate total allowable oxygen exposure for a day.

The course book is organized like the larger book for the initial PADI Open Water class. You read, you underline and you answer questions at the end of each chapter. The idea is not necessarily to memorize every word, but to grasp concepts and know where to look things up. The answers are always given, on the same page, in small print. At the end of each major section is a "knowledge review" that you fill out and sign. No answers given there. Studying and understanding all the materials takes some time, and then doing all the dive table examples takes some more. It's not necessarily very difficult, but it is important stuff that people from all walks of life need to understand before they go diving with Nitrox. Bottom line: you need to set aside several hours of concentrated worktime to prepare for the class.

The class itself was full. 12 people at least in a small but neat and well organized and equipped classroom. Our instructor was Rick Rowett, a PADI course director, which is as high as it gets in the PADI hierarchy, and also the manager of the Dolphin scuba store. And, as he later told us, a reverend. Rick was personable, knowledgeable and did a great job. The class essentially consisted of going through all questions of both Knowledge Review sections, with detailed explanations if someone had gotten it wrong or did not understand. A good approach, assuming everyone had indeed done their studies beforehand. Rick threw in a lot of explanations, advice, and anecdotes, making it all flow nicely and having great rapport with the class.

The second part of the Knowledge Review included several dive table questions, and we worked through each and every one of those in detail.

Once that was done, we signed a general liability release and were issued the final test that consisted of 25 multiple choice questions, including several that required the dive tables and a calculator. Those were not idiot questions and required some thinking. Once finished, you joined Rick in the next room where he demonstrated the use of an oxygen analyzer. You then got to use the analyzer yourself and entered the requisite data into a log book, just as you would when you get a Nitrox fill.

After everyone was finished and had done the hands-on with the oxygen analyzer, it was back to the classroom where we went over all the questions. Once again, Rick explained each answer and went into more detail if someone had gotten it wrong. I got 24 of 25 and stumbled over a trivial one. No big deal.

Thing is, unless you really, really goof, you can't fail. You no longer have to hand in the signed knowledge reviews that are part of the course book (and bound in). Apparently, you also cannot fail in the final test; at the bottom is a statement that says something like, "I have gone over the answers I got wrong and now understand the question and how to answer it properly," and then you sign that. And there are no dives involved. So you don't get to experience the difference between compressed air and Nitrox under the guidance of an instructor. No big deal, really, as Nitrox is becoming quite common.

I think I have mixed feelings on this. While Nitrox has been used for a hundred years or so, its use in recreational diving is relatively new. Initially and from what I am told, PADI and NAUI were quite opposed to it. Early course materials included true but rather discomforting statements like "you can die," and even the current course book has sort of a "not invented here" tone to it. It feels a bit like Nitrox is a subject that the certifying agencies were forced to include because the lure of longer bottom times (and feeling better after dives) were such that recreational divers simply wanted to do it.

If used improperly, Nitrox can be dangerous, but that goes for a lot of stuff in life. Anyone can walk into a car dealership and buy a 500-horsepower Corvette or Viper even though such vehicles can be vastly more dangerous than, say a Toyota Camry. There is no "Corvette" certification needed (actually, good thing PADI doesn't run the Department of Motor Vehicles...). So it comes down to common sense.

What makes it all a bit more confusing is dive computers. Sure, understanding the theory behind Nitrox use, and being able to figure out a problem on old-fashioned dive tables, is a good thing, but these days divers rely on dive computers. They may take a look at the maximum depth for their Nitrox mix, but then solely rely on what the dive computer says. And that's a big problem because dive computers are definitely not standardized. It can be next to impossible to even figure out if a dive computer can handle Nitrox unless you have the instructions at hand (and who does?) and that the instructions are halfway intelligible (they often aren't). So you take a class to learn Nitrox diving with dive tables, but then virtually everyone uses their dive computer and may not have a clue how to even set it to Nitrox. A definite weakness in the armor there.

In any case, I am hugely pleased that I finally have my Nitrox certification!

Posted by conradb212 at 11:19 PM | Comments (0)

September 12, 2007

Nitrox

Today I am going to take the PADI Nitrox class. Attending the class and passing the exam will allow me to use Nitrox when I am diving. Interestingly, actual dives are not required with the class - it is all academics. You buy a "Nitrox crew pack" that consists of a textbook with questions, a DVD that illustrates what is in the textbook, and three special dive tables for Nitrox.

What is Nitrox? There are various definitions. Nitrox is something that almost no one who isn't a diver has ever heard of. And even if you explain it to a non-diver, the whole theory behind it is such that they're likely just going to shrug their shoulders. Hmmm... Nitrox. Interesting. If that.

So what is it? Well, it's a special air mix where the percentage of Oxygen versus Nitrogen is different from that of the regular air we breathe. Regular air consists of about 21% Oxygen, 78% Nitrogen, and one percent of various trace gases (mostly Argon, but also a tiny bit of Neon, Helium, Krypton, Methane and a good half dozen others). Divers generally consider Nitrogen an "inert" gas because our body does not metabolize it. A better description is that Nitrogen is generally inert. There are, after all, things like Nitrous oxide -- N2O -- which is also known as "laughing gas" because of the mild euphoria and analgesia it caused in dental patients. It's also been used as an aerosol in spray cans, and street racers use it to gain more power from their engines as it delivers more oxygen than regular air, and thus allows more fuel to more burned.

None of this matters to divers who do consider Nitrogen an inert gas. Unlike Oxygen, our body does not use it up. However, Nitrogen does play a very important part in diving anyway. That's because it is absorbed into our systems, and that absorption is pressure-related. This absorption is not an issue under atmospheric pressure. Our bodies are in a state of nitrogen saturation, our tissues absorb so and so much nitrogen and that is that. That all changes when the pressure on our bodies is increased or decreased. Decreasing pressure, as in going from sea level up to the top of a mountain where the air pressure is less is rarely an issue as pressure simply goes from one atmosphere, or roughly 14.7 pounds per square inch (psi), to maybe 10 or 12 psi at considerable altitude. It is very different when we dive. The pressure on our body increases by a full atmosphere for every 33 feet of depth. So if we dive down to 33 feet, it is already twice what we experience at sea level, and at 99 feet four times as much. And since dives don't generally last very long, we go from standard atmospheric pressure to several times that and then back within an hour or so.

What does that mean? Well, several things. When we dive, the air we breathe must counteract the water pressure pushing in on our bodies. So at 33 feet, though breathing feels no different, the pressure of the air supplied by the regulator is actually twice that on the surface. We don't really notice that due to Boyle's law that says as gas pressure increases, its volume decreases. The composition of the air, however, does not change. Even under pressure, it's still roughly 21% oxygen and 79% nitrogen. John Dalton figured that out over 200 years ago. Around the same time, another brainiac, William Henry, found that the amount of gas that will dissolve in a liquid is a function of its partial pressure and how easily the liquid absorbs gas. So what do we make of all that?

Well, if we go down to 33 feet, the compressed air we breathe still consists of 21% oxygen and 79% nitrogen, but its pressure is twice as much as on the surface. That means we now inhale twice as many oxygen molecules and twice as many nitrogen molecules. How does the body react to that? As far as oxygen goes, it simply takes what it always takes and the rest is breathed out by exhaling. Even at sea level, humans do not use all the oxygen we inhale in a breath. In fact, it's only a quarter of it or so (else doing mouth-to-mouth resuscitation wouldn't help at all). Down at our 33 feet, we still use about the same number of oxygen molecules, the rest goes to waste (a phenomenon which, of course, is exploited by rebreathers).

Nitrogen, that's another story. As a mostly inert gas it simply gets absorbed into our body tissues in compliance with Henry's law. So as we go deeper, more nitrogen gets absorbed into our body tissues. Not all absorb at the same rate -- some are "fast" tissues and others are "slow" tissues. The software program that I use with my UWATEC dive computer, for example, shows how the various tissue "groups" in my body absorb or release nitrogen during the various stages of my dives.

Now nitrogen, inert though it is considered, does two things. First, while absorbing more of it into our bodies during a descent doesn't do much, releasing the gas again as we ascend is another matter. If we ascend too quickly, the body "off-gases" the absorbed nitrogen in the form of bubbles. If all goes well, those bubbles are tiny and simply go through the blood stream into our lungs where they are safely exhaled. However, rapid pressure decrease can result in bigger bubbles and they can get stuck in the blood and block passages, or they can lodge in inopportune places like joints, the skin or elsewhere. That can have dire consequences. The dreaded "bends" is one. And the bends can range anywhere from discomfort to death.

The second thing nitrogen does is exhibit a narcotic effect if its partial pressure becomes too great. Partial pressure means the pressure the gas represents of the total pressure in a gas mix. Nitrogen's partial pressure is about 71% of the total pressure of air at sea level. As we dive, nitrogen's pressure stays the same in terms of percent, but at 33 feet that 71% is now twice as much in terms of absolute pressure, so we breathe in twice as many nitrogen molecules with each breath. As we go deeper yet, that partial pressure of nitrogen somehow interacts with our nervous system and causes a narcotic effect called "nitrogen narcosis" or, by more poetic souls, things like "rapture of the deep." While that may have its pleasant aspects, being what really equates to being kind of drunk while diving at, say 120 feet, isn't a very good thing.

So this is where Nitrox comes in. When most divers say "Nitrox," they mean air that has a larger percentage of Oxygen and a smaller percentage of Nitrogen. What does that do? Well, with less nitrogen in the breathing mixture, less will be absorbed into the body. If you dive with Nitrox to a certain depth, it's really like diving with air to a lesser depth. Anyone who took the basic open water diving certification classes is familiar with the dive tables. They are about how long you can stay under without having to make decompression stops so that the absorbed nitrogen can be released safely. With less nitrogen, less is absorbed. And that means you can stay down longer. If you stay down the same amount of time as with air, and at the same depth, and then come up, you have absorbed less nitrogen and need less of a surface interval, if that matters to you.

So it's all good, that Nitrox stuff. Well, yes, mostly. But everything comes at a price. With Nitrox it is not only the higher price of a tank refill (they need to create that different kind of air somehow; it cannot just be run through a standard air compressor), but also what another gas can potentially do to us. And that gas is Oxygen. Yes, life-giving Oxygen can also be toxic. How so?

As we go deeper and the partial pressure of Oxygen increases, it can have its own effects on the body. It can make you experience a bunch of syndromes such as tunnel vision, ear ringing, nausea, euphoria or anxiety, dizziness, and twitching or muscle spasms. Those are all warning signs of impending CNS, or central nervous system toxicity. That generally leads to convulsions and you drown. Very bad.

So we have to watch oxygen as well. The partial pressure of oxygen in air on the surface is 0.21 atmospheres. At 33 feet it's 0.42. And at 66 feet 0.63. It's been determined that the maximum safe partial pressure of oxygen is about 1.4 atmospheres, with brief "contingency" exposures of 1.6 acceptable. With compressed air, we get there well past the recreational diving depth limit of 133 feet, so it is not generally an issue when you dive with compressed air. With Nitrox, it's different. Two common Nitrox mixes contain 32 and 36% oxygen. With a 36% oxygen mix, usually called EANx36, we reach that 1.4 atmosphere barrier at just under 100 feet. You can see the problem here, and you can see why divers who want to use Nitrox and take advantage of the longer dive times it affords need to know about all this and the theory behind it. Sure, dive computers take care of it, but you need to understand how it all fits together.

And there's more. While air is air is air, with Nitrox there can be errors. If you think you're diving with 32% oxygen in your tank but, in fact, it's 42%, things can go real bad quickly if you go deeper than you should. So one of the cardinal rules of Nitrox diving is that the diver MUST test the Nitrox mix personally, with an oxygen tester. There are also mandatory records and labels to provide extra safety and accountability.

But even that is not all. Oxygen can be dangerous. It can ignite in pure form, or even when it is present in high concentration. The crew of Apollo 1 perished in a flash fire when a spark ignited the pure oxygen in their capsule. Some filling methods use pure oxygen which is then diluted until the proper mix is reached. So tanks used for Nitrox must be "oxygen-safe." Depending on the oxygen mix, other parts of the equipment, such as regulators, may also need to be oxygen-safe, though the kind of Nitrox recreational divers use does not require anything other than a dedicated Nitrox tank.

So I will soon find out about Nitrox and how it feels. Carol swears by it and uses it almost exclusively. Like many Nitrox divers, she feels less fatigue after a Nitrox dive, and she generally feels better. Me, I have only done a few dives and have not been subjected to to the rigors of lots of repeat dives, so I guess I'll find out.

Posted by conradb212 at 11:19 PM | Comments (0)

August 28, 2007

Limited Lifetime Warranty

I must admit that my view of warranties, and my faith in them, is not the best. When I hear "warranty," what comes up in my mind is not a security blanket or the warm fuzzies associated with knowing that I am covered should anything ever happen to my equipment, whatever it may be. Instead, it's mostly feelings of frustration, sarcasm, and at times anger, the kind consumers experience so often. We've been had. Sure, almost anyone will be able to tell of a wonderful experience of warranty replacement and service, and I have some, too. Not many, unfortunately, and that's the problem right there. But I'll relate those anyway, just to be fair: Far and away the best experience in terms of warranty I've ever had was with CostCo. When an almost brandnew Aiwa projection TV stopped working after a few weeks, they gave me a new one, no questions asked. When the new one also crapped out shortly after that, I got another new one, and that one still works, after several years. You might say CostoCo's action was more replacement policy than warranty. I am pretty sure things would have gone a lot less smoothly had I had to take matters up with Aiwa. In any case, as a result of CostCo's terrific handling of my problems, they have a customer for life.

Car warranties? Hah! They almost always find a way around paying for warranty repairs. Or they get you in some other way. So much so that I never go back to the dealership after I buy a new car. The hassle is just not worth it. Supposedly reputable companies like Best Buy who constantly bleat about their service? Well, they were unwilling and unable to repair a three-year-old TV as "the parts are no longer available." Then some independent quoted an absurd fee to just look at it, and Best Buy helpfully offered to sell me a new one. So I googled and diagnosed the problem, and fixed it myself.

What does all that have to do with Scuba? A lot. The several thousand dollars' worth of Scubapro gear I bought last year has lifetime warranties. That is certainly good to know, though lifetime warranties are always a little suspect. Five-dollar tools have them, but replacement generally means $8.99 or so in shipping and handling.

No, my Scubapro gear did not fail, but it was urgently brought to my attention (not by Scubapro where my gear is registered, btw) that I needed to have my gear serviced or else I'd lose my lifetime warranty. Lose it? How? Well, read the fineprint and conditions of the Scubapro Limited Lifetime Warranty and you find that Scubapro only warrants the product for a lifetime "with reasonable maintenance."

What does "reasonable maintenance" mean? It means "... as a minimum, annual servicing in accordance with recommended Scubapro maintenance procedures or their equivalent and performed by an authorized Scubapro dealer." Should you ever need warranty repair, you need to produce the original Scubapro ID card that comes with the equipment and the name of the authorized Scubapro dealer who performed the last annual service, or no warranty service for you, buster. With those requirements, no car I ever owned would have qualified for warranty repairs. Oh, and if service was ever performed by anyone other than an authorized Scubapro dealer, you're out of luck as well.

Anyway, apparently my Scubapro gear had to be serviced or else I'd forever lose my warranty. Unfortunately, as reported a long time ago, my own Scubapro dealer folded three days after I bought all my equipment from him. My local diveshop here in Folsom had been unable to convince Scubapro to bestow dealership status upon them. And so I had to look elsewhere for proper service. Which I did.

I went to the Dolphin Scuba Center, a 65-mile round trip for me, to drop off my equipment for service. "Drop off?" you may ask. "Why didn't you just schedule an appointment, went in and waited while they checked your regulator?" Well, see, that is not the way it works. You drop your gear off and then it may take a week or ten days, or maybe more until they call you. Could be less, could be more. To be honest, that sure surprised me. And, also to be honest, I don't like it one bit. What if a dive trip opportunity came up during this unspecified period of time? Sure, I could probably get rental gear, but I like mine. Anyway, after much paperwork, and an estimate of US$75 to service my Scubapro regulator and AIR2 backup, my gear was carried off to the service department.

All that said, the Dolphin Scuba Center off Highway 80 on El Camino Avenue in Sacramento is awesome. A very large scuba store with so much equipment that I ended up spending two hours just looking around and buying a few things. A friendly owner who introduced himself and talked to me. All good. And I even understand that something your life may well depend on requires extra-special service. Maybe I am too suspicious and too gun-shy when I see so much legalese. But I still do not like to have to wait ten days or two weeks and having to make two 65-mile round trips just to have a regulator service.

Posted by conradb212 at 11:18 PM | Comments (0)

August 19, 2007

The Folsom Outhouse

Though not ever destined to achieve the notoriety of Folsom Prison, the Folsom Outhouse is nonetheless remarkable in its own right. Only in California, I suppose, but I'll get to that in a minute.

I was supposed to go diving yesterday. The local diveshop had organized a community service project in the form of an expedition to lift a Toyota 4-Runner out of the American River. Seems there is a rocky place along the American river shore, not that far below Folsom dam and just above Nimbus dam. People jump off a cliff there, hurt themselves, and dump all sorts of stuff. Bicycles are said to be there at the bottom of the river, and apparently a Toyota truck. And maybe some guns or ammo or whatever. The truck somehow fell in, or was pushed in, about three years ago. No bodies or anything, but also not a real good thing. So the owner of Divers Cove in Folsom decided it should come out and organized the whole thing.

I had stopped by the shop Friday and they were testing the lift bags. Two long ones with a lift capacity of 2,000 pounds each, and then a big cushion-like one with a capacity to lift 4,000 pounds. Now a Toyota Forerunner weighs perhaps 5,000 pounds or so, but that's on land. In the water it only weighs the difference between the water it displaces and the water itself. So those lift bags were plenty enough to get the Toyota out of the muck and float it back to a dock.

So on Saturday I packed my gear and headed for the dive shop with Morgan, my 11-year-old son. A good number of people were already there and loaded stuff on pickup trucks. Lots of air tanks. Rigging of all sorts. More people trundled in, some seasoned divers, others recently certified and in need of rental gear. Robert Flores then had everyone sit down at the big conference and training table, cranked up his projector, and used Google Earth to show the dive location and explain the dive plan. He did a marvelous job, all concise and to the point. But it also became clear to me that we could not go. Diving meant boarding a boat to get upstream to the site, and only divers could get on the boat. I was not about to leave my son behind in some park all by himself. Besides, cold water, a current and very low visibility didn't exactly sound too appealing. So Morgan and I decided to go to Folsom Lake instead.

Folsom Lake was where I'd done my certification dives a little over a year ago, but it was hard to recognize the place. Since it is a reservoir, Folsom Lake goes up and down a lot, and this summer the water level is way down. All the boats from the big marina had to be moved to dry land and were filling the parking lots. Not much fun for them. When I had done my C-dives, it'd been fun to dive and look down onto a parking lot. Well, that parking lot was all dry now and we parked there. And not only that, but the lake level was now much lower than the parking lot so that the shoreline was totally different.

Morgan and I decided to take a hike along the shore, which isn't that much fun since the surface is either muck or really sharp crushed rock. He thinks it's hysterically funny to sink calf-deep into the muck in new sneakers. Me, less so. Anyway, we made it a good distance and around some bends and there it was, the Folsom Outhouse. I know, that doesn't sound too terribly appealing, a floating outhouse, but it really wasn't just a floating port-a-potty like they have at construction sites or county faires. This was a neat, tidy, floating structure, nicely anchored perhaps 50 feet off-shore. I am not sure if they relocate it if the lake level is higher or lower, but for now that's where it was. And it just looked so bizarre and comical, floating there that we couldn't stop laughing.

Morgan then went into the water, with all his clothes on, and paddled around. It got deep quickly, but he is a good swimmer and diver. He really wanted to swim over to the Outhouse and check it out, and so I told him he could go. I'd have gone with him, but I had stupidly taken my valuables and other non-waterproof stuff with me and didn't want to leave them laying on the shore. So Morgan swims over to the Folsom Outhouse and tries to lift himself up onto the surface, but it is too high. He tried for a few minutes, then swam back. Shortly thereafter a motorboat approached and docked, and a whole procession of people boarded the Outhouse and used its facilities. Morgan saw the presence of the newcomers as an opportunity to get a lift onto the Outhouse deck and I literally had to hold him back as I didn't want him to crash the pooping party.

So we waited until they were all pooped out, then he swam back and tried again. To no avail.

Why is it there, the Folsom Outhouse? Well, I suppose it's better than to stand on the boat and pee in the lake, but the lake isn't all that big and a suitable facility is likely within five minutes' distance for a motorboat. And it's clearly not for swimmers as there isn't a ladder or anything. So the Outhouse remains a mystery, at least to us. Who did it? How did it come about? How do they maintain it? I guess it's a California thing.

Posted by conradb212 at 11:18 PM | Comments (0)

August 14, 2007

Diving the Wall off Rubicon Point, Lake Tahoe

After diving Meeks Bay with its terrific visibility, it was now on to another Lake Tahoe dive site, Rubicon Point at the D. L. Bliss State Park which is just north of Emerald Bay off Route 89. Rubicon Point's claim to fame is a wall dive, with the rock wall falling almost vertically down to over 800 feet.

D. L. Bliss is a large park and the entrance is high up in the mountains and easy to miss. You also want to get there early as the park fills up quickly for campers, and there are only so many parking spots. Entrance is $6, and the park ranger will ask you what you intend to do so they can steer you in the right direction. For diving you want to go to Callawee Cove. After a couple of miles of up and down driving through pristine forest we get to the Callawee Cove parking area that has maybe 15 parking spots. From there it is a steep trail down to the beach with 55 steps. Not something that is a lot of fun to negotiate with full dive gear on, and we brought huge 130 cubic foot steel tanks!

So we suit up and this time we take along a dive flag float, hoods and gloves. Getting all that gear down to the small cove is challenging enough, but even as we go down we wonder how we're supposed to get it all back up after the dive when we're cold and exhausted and not supposed to exert ourselves too much.

The water was absolutely crystal clear at the beach and the temperature about 68 degrees. From the parking lot we had seen the usual brilliant blue-green water of Lake Tahoe, but also darker parts and I wondered if that was algae. Turns out it wasn't; it was just clean black sand.

Even after making my way down to the beach it took me a while to cool off and calm down enough to get all my diving gear all set, including the hood and my gloves. I am not used to a hood, and I don't like it any better than wearing a helmet when I race cars. I don't like the constriction and the restricted visibility. And it took me forever to get on my gloves. Sometimes I wonder why all Scuba gear seems to fight you as you put it on. Even though it is not mandatory in California, I am glad we brought the floating dive flag as it doubles up as a carry bag and repository for whatever you don't need at the moment. We also had brought two new underwater cameras to test, the 6.0 megapixel SeaLife ECOshot and the 6.1 megapixel Sealife DC600.

From Callawee Cove you can do all sorts of diving, from hanging around above the shallow sand bottom to spectacular rock areas and to the Rubicon wall. The wall dive is off Rubicon Point - perhaps a 100 yard swim or dive to the south. There isn't much of a current and so it's no big deal. Personally, I recommend diving from Callaway Cove to the Point if you have enough air. There are plenty of cool rocks and boulders in clear, shallow and totally clean water. It does, however, make sense to take along a compass and get a bearing.

With the big 130 cubic foot steel tanks, air was not going to be a problem. In fact, Robert Flores of Diver's Cove in Folsom had urged me to keep an eye on remaining no-decompression time and not just remaining air. He said it was all too easy to get caught up in the fantastic vistas, become over-confident because so much air is left, and lose sight of remaining bottom time. I certainly kept that in mind. If anything, I tend to check my dive computer too often, and Carol, with her many years of experience as a NAUI instructor and technical diver, is a total expert. The big tanks, it turned out, made us a bit bottom heavy but it was manageable.

I had no idea what to expect from Rubicon wall. The site is generally described in glowing terms, with some going as far as praising it as one of the great dive sites in the world. Many call it the best dive site in the entire Sierras, and the best wall dive in Lake Tahoe. The lake's exceptional visibility is a big attraction, of course, as is the wonderfully clean and clear water, and the gorgeous scenery around the lake in general.

Based on what I had seen at Meeks Bay just a few miles north, I expected a fairly shallow sandy bottom and then all of a sudden a vertical rock wall. Given the topography, I thought it was also possible that rock formations above the surface might just continue dropping underwater. From what I read, the wall goes all the way down to 800 feet or so, which of course means that no scuba diver has ever seen the bottom. The topographic map of the lake looks like it might go much deeper than that, to over 1,400 feet. I also wondered at what depth the wall began. Was it at 30 feet or 80? And where were we supposed to look for it?

What happened was that we swam on the surface to Rubicon Point and then descended onto the sandy bottom at about 18 feet. As we headed south-east, the sand gradually and then more quickly gave way to more and more huge boulders and a much steeper slope. At about 40 feet, the temperature began dropping rapidly as well. At the surface it had been a relatively balmy 66 degrees. After a six minute descent to 60 feet it was down to 60 degrees. I had both the ECOshot and the Sealife DC600 cameras strapped to my right wrist and alternated between them taking pictures.

At 68 feet, all of a sudden I saw this huge boulder cliff ahead of me and beyond that just open water without anything in sight. It felt a bit like walking up to the edge of the Grand Canyon, only without seeing the bottom or the other side. I very gingerly approached it, thinking that perhaps I just wanted to lay on top of a boulder and peek over it, holding on. Carol was already floating over the abyss and so, after taking a deep breath, I followed. At first it was a very strange feeling to just float out into nothingness. All your senses tell you that you must fall, even though you're diving. But I did not fall. I just hovered over the edge of the great wall, hanging in the water.

We then slowly descended down the wall which really wasn't a cohesive wall as I had thought, but a very steep, almost vertical, descent with huge rock sides that seemed granite and did not have a lot of features or anything to hold onto. It was a bit spooky but I didn't freak out and never even came close. I might have felt more intimidated had I looked up, but I still don't like to look straight up when I am diving. Somehow, that disorients me and I get water in my ears which seems strange as the ear canals presumably are already pretty full of water. Perhaps turning your head shifts air and water in your ears. Whatever it is, I don't like it.

By now we were at 90 feet or so and then 100. I felt fine though it was rapidly getting colder now, with my dive computer indicating 48 degrees.
Once I reached 100 we were in sort of a steep valley and so I decided to go for 110. I signed Carol that I wanted to go down to 110, but didn't do it properly, holding up five fingers, then five again, then one. I carefully descended to 110 feet, keeping an eye on my dive computer, then went back up to 100. Carol gave me the "I am cold" sign and motioned to go back up. So we began ascending the great wall, taking our time and going up very slowly. At 60 feet the dive flag string got caught up somewhere and we had to undo that. At 50 feet we did a five minute stop, entertaining ourselves by examining a big crawfish in its hole. I checked the Sealife ECOshot test camera. It was fine. It is rated at 75 feet but easily survived the trip down to 110 feet.

We had decided beforehand that we'd take it easy and do all the suggested decompression stops so that the nitrogen could dissipate from our systems. Theoretically, we did a no-decompression dive, but altitude diving is different and a decompression stop is urged. We did that by leisurely navigating back to Callawee Cove at depths from 15 to 8 feet. All in all it had been a 65 minute dive. Carol still had almost half her tank left; I had used considerably more, but was nowhere near empty.

Despite wearing hoods and gloves, the much lower temperatures we encountered did a number. We were shivering and welcomed the balmy 80 degrees at the beach. We just sat there, reveling in the experience we had just had, then washing off and getting ready for the daunting climb up to the parking lot. Heavy exertion after a strenuous dive is a total no-no, and so we made sure to take it as easy climbing up the steps as possible. I took just a few steps at a time, but was still huffing and puffing by the time I was back up.

Much later, after I had uploaded the data from my dive computer into my laptop, I saw something that made me think. I had, of course, monitored my no-stop remaining bottom time. At 110 feet it had been four minutes, then it gradually increased to eight minutes as I ascended and then ten minutes at 60 feet. However, when we made our five minute deco stop at 50 feet, it went down to just one minute and then stayed between two and five minutes until we reached 28 feet when it all of a sudden jumped to 99 minutes.

I wish I understood the computer's reasoning better. If at 110 feet I have four minutes of no-deco time, I thought I'd have much more at 50 feet. I understand the four minutes; the PADI Recreational Dive Planner suggests a maximum no-deco time of 16 minutes at 110 feet, but since due to the altitude I started out as a PADI "C" diver and since high altitude dive tables applied, the actual bottom time would be much less. The operating manual of my UWATEC SmartZ dive computer issues a warning to never allow remaining bottom time to go below three minutes. If it goes below, the manual warns of dire consequences. It then suggests to ascend slowly until the no-stop time goes to five minutes or more. The only explanation I have of why my no-deco time dropped so much is that on the way up I swam under a rock that jutted out instead of around it. That got me from 61 feet back down to 74 feet. I am also not sure why at 28 feet, all of a sudden all bets are off and the no-deco time jumps to 99 minutes.

In any case, this was an incredible dive and adventure.

Posted by conradb212 at 11:17 PM | Comments (0)

August 13, 2007

Diving Meeks Bay, Lake Tahoe

So finally it was time again to go dive. I had planned to get up bright and early and leave at 7AM or so for the 100 mile road drive from Folsom to Tahoe, but it's just amazing how much stuff one needs to tag along for a dive trip. The day before, I had a second car key made at a local hardware store, one without the transponder built into the plastic FOB of almost every new car these days, and used a key ring to securely attach it to the BC. All in all it was almost 10AM by the time the PT Cruiser was finally on the road and headed on up Route 50 into the Sierra Nevadas. It was a beautiful sunny morning and the drive up the winding mountain roads was glorious. 4000 feet, 5000 feet, 6000 feet, 7000 feet, and then pass the summit at 7,420 feet. The lower pressure at that altitude meant, according to PADI, that I was now off-gassing and basically equivalent to a diver emerging from his initial dive of the day, and finding himself in the PADI dive table pressure group "P."

The first peek at Lake Tahoe from high up is always breathtaking, and this day the air was so clear that it sparkled in a deep, deep blue and you could see forever. For a while Route 50 and Route 89 go together towards Lake Tahoe, then, once you reach the lake, 89 goes up north along the Western shore of Lake Tahoe, up and down the mountain sides with such majestic vistas that you feel tempted to stop again and again to take pictures. We did have enough cameras on board for that, of course, and so it was almost noon by the time we'd successfully located the small Meeks Bay park about five miles north of Emerald Bay. There is no ranger station, but just a machine that spits out a ticket in exchange for a five dollar bill. That's more than fair for a day's worth of fun at Lake Tahoe. I had been a bit concerned about finding parking as there are but a couple dozen spots, but we all got lucky.

So then it was time to lay out the diving gear and for me to begin the usual struggle with my 7mm Telos wetsuit. Though it was only 80 degrees or so, the sun was burning down and the air at Lake Tahoe -- 6,230 feet above sea level -- is a good deal thinner than I'm used to. After a lot of grunting and the occasional swearword or two we're all suited up, steel 95s on our backs, and we walk on over to the beach.

We see a trio of divers that had just returned from a dive and so we stop by to say hello. At Tahoe you know the visibility is great -- no need to ask -- and so we inquire about the temperature instead. 67 degrees Fahrenheit at the surface, but just 55 or so at 90 feet they say. Yes, hoods and gloves would be a good thing; they'd worn them. We'd brought those along, but it's hard to see them as necessary when you're sweating like a pig and about to have a heatstroke, so they remained in the car. All I heard was 90 feet. They had actually gone down the slope to 90 feet at Meeks Bay?! I remembered the sandy, featureless drop descending at a 45 degree angle and how it had felt a bit scary for me to descend to 58 feet last Fall.

A good number of people enjoy the pristine beach, but it isn't too crowded. We can't wait to get into the clear water and it does feel good. I cool off, recover from walking from the parking lot to the water in my wetsuit and all my gear, put on my fins (still always a struggle after all this time) and then it's time to go under. I carry 12 pounds of weight total -- two 4 pound bags in the left and right pockets of my weight-integrated Scubapro Knighthawk BC, and two 2 pound baggies in the back/shoulder pockets of the BC.

We descend to the sandy bottom at 15 feet or so. I am breaking my own rule of never wearing a new (to me) mask on a real dive by using one that has built-in corrective lenses so I can better see my dive computer and the controls and screen of my camera. It's an interesting design, with the bottom of the mask lens consisting of two magnifying pieces of glass at an angle so you can look down at your instruments or dive computer. I give it a quick test. I can clearly see and read the LCD display of my UWATEC SmartZ dive computer, and also the tiny controls of the Olympus 770 SW underwater camera I'd brought along. The mask isn't fogging up and it seems to have a good enough fit for the shape of my head that it doesn't leak. However, the straight lines where the two glass panes meet is distracting and I have to tilt my head more, and can see less, than I expected.

Someone apparently had some fun on the sandy bottom. Perhaps decompressing, they'd written "BE GOOD" with brick-sized rocks, and also "GT" and I wonder if that is in reference to a diver's car (such as my PT Cruiser GT). But on we move, out to the buoy where we're supposed to take a right so as to stay clear of the marina with its boats. Meeks Bay is on the California side of Lake Tahoe, and so a dive flag isn't required, though the regulations -- which I had looked up -- are exceedingly murky and confusing.

The water feels good. Cool and refreshing rather than cold. About eight minutes into the dive we reach the slope, but it isn't like what I had seen last year. It's not the sandy, featureless 45-degree slope. Instead, we're farther south where the huge rocks and boulders are. I look around and it's beautiful. The visibility must be over 100 feet. I hover amidst hundreds or thousands of glistening little fish, schools of minnows perhaps. It feels like sitting in an IMAX theater and watching an underwater movie where the fish are all around you and you feel you can just reach out and touch them. Except that this is real. But instead of your hand going through the 3D IMAX fish, these live ones simply dart out of the way. I could have just hung there in wonder, watching those fish and the giant boulders.

But we move on and are now on a rather steep slope with huge boulders, very different from what I saw last year. There is apparently more to Meeks Bay than I first though. It is not just a simple beginner's dive.

For some reason I am not 100% comfortable. The mask with its optical inserts narrows my field of vision, something which I don't like at all. I take some pictures with the Olympus 770 but don't pay much attention to it. We stop at around 70 feet, deeper than I had ever gone before. I still don't feel quite right. The visibility is great, so that is not it. But as we stop I am very aware that we have 70 feet of water above us and for a moment I wonder what would happen if something went wrong with my body or I panicked. Staying put gives me time to think about this and I don't like it. So I hover and swim around to shake off the uneasiness until it's time to move on.

We're going deeper and it's getting pretty cold now. My dive buddy gives me a sign but I can't quite figure out what she's trying to tell me. She motions for me to follow, but I am at 94 feet already and don't feel like descending deeper. She does, takes a picture with her Casio S500 in its deepwater case, then returns and points at her dive computer. She'd gone to 100 feet in Lake Tahoe. Given that we would have to return up to the 7,440 foot summit, which is rounded up to 8,000, 100 feet represents an altitude-adjusted depth of 134 feet in the Altitude-Adjusted Dive Depths tables. Later I'd wonder if perhaps I'd felt a bit of nitrogen narcosis. I didn't feel weird or euphoric or paranoid, but it also never occurred to me that I was holding the Olympus 770 camera in my hand, the one rated at 33 feet but that had accompanied me without ill effects down to 67 feet at Manatee Springs State Park. This was almost 30 feet deeper.

For the next ten minutes we slowly ascend, weaving our way through and around all those rocks and boulders until we're back up at 30 feet. The temperature quickly rises from 55 to 66 degrees, but by now I am cold. We again see the schools of little silvery fish and occasionally a bigger one, and some pretty sizable crawdads. They are usually feisty fellows, swinging their claws at us and definitely not willing to give an inch.

We continue exploring for another ten to 15 minutes at around 20 feet and then it happens: I am unable to dump air from my Knighthawk BC and feel myself rising. I hold up my Air2 with its dump valve, but no matter how hard I push, no air comes out. I try to swim down, but it's too late. I am already at the surface. No real big deal, but I am upset with myself!

Now I am really cold, with my whole body just shivering away. We get out of the water, and then just sit for a while, recovering. It'd been a great dive. There aren't too many places with 100+ feet of visibility, grand underwater vistas, the ability to go as deep as you're comfortable with, and it's all easily reachable from the shore. In addition, the water is crisp and clean and clear. What more can one ask for?

Posted by conradb212 at 11:17 PM | Comments (0)

August 06, 2007

First Scuba certification anniversary and diving Tahoe again

Time flies. Exactly a year ago I received my PADI Open Water certification at Folsom Lake. It seems like a lifetime ago. I look at the picture of my instructor, Chuck Odell, with his arms outstretched, proclaiming, "You are now certified!" Back then I didn't know what to expect. Everyone had told me about the camaraderie among dive class graduates, and how we should keep in touch and go dive together. And, of course, how our local dive shop, the place where we learned and got certified, would have all those trips and opportunities. Well, my class, small to begin with, showed no interest in keeping in touch. I tried, sending everyone emails, but that all quickly fizzled. And my dive shop went under a few days after I got certified. Sure, some of the folks who got stranded when the dive shop tanked got together and formed their own loosely knit group. I even did their website and attended the initial meeting. But they were mostly couples who had known, and vacationed with, each other for decades. I probably could have become part of that group, but for whatever reason, I didn't.

So it's a year later, and as with everything else in my life, I don't know whether I succeeded or bombed. I certainly didn't drop out of diving like so many newly certified divers do. I do have 27 dives in my log book, and have spent a total of 806 minutes underwater, 13-1/2 hours. I got my advanced NAUI certification, and have seen some very interesting places. And the scubadiverinfo.com website certainly has grown. I've written some 65,000 words of blog entries alone, and site traffic keeps growing. On the negative side, it's a year later and I have just 27 dives under my belt (or integrated weight system), and four of them were the certification dives. That's not exactly a whole lot in a year, and I still haven't even tasted salt water. All my dives have been in lakes and rivers and sinkholes. I certainly read and learned a lot, and it's been a thoroughly interesting experience. But not having a local dive buddy certainly meant fewer dives than I had anticipated.

But now the next trip is planned. It's Lake Tahoe again. SeaLife is sending me three of their latest underwater cameras for review, and the big Olympus Evolt rig certainly needs to get back in the water. I also have four other new cameras that need to be reviewed, and what better place than Tahoe?

So that means I have to think about high altitude diving again. Sadly, I never did get the PADI high altitude diver card Chuck had said I had earned. I reminded him a few times, but life got in the way, and I think he moved elsewhere. Oh well. In any case, I've been thinking about high altitude diving and what it means.

It's actually an interesting topic with several aspects. I had given it a lot of thought last year before I dove Tahoe with Chuck. So much that his curt reply to my long email was "You're overthinking!" Well, as far as I am concerned, that's better than underthinking. Anyway, the issue with high altitude diving is that the sea level dive tables don't apply. Why is that?

Well, Lake Tahoe is at 6,230 feet, and at that altitude, the air pressure is only about 80% that of sea level. So if you dive down to, say, 66 feet, the 66 feet of water add the usual two atmospheres of pressure. But when you ascend again, you don't go from the usual three atmospheres to one, absolute. Instead, you emerge to an air pressure of only 0.8 atmospheres. So as far as nitrogen absorption goes, it's as if you had done a dive not down to 66 feet, but to 1.2 times 66 feet, or 80 feet. But, you may say, what if prior to the dive you had stayed at high altitude long enough to have off-gassed enough nitrogen to be at an equilibrium? Admittedly, to my way of thinking, the 66 foot dive should then be just a 66 foot dive. But that's not the way high altitude dive tables see it. In fact, they're even based on not only the water level of where you are diving, but the highest elevation you'll be going 24 hours after a dive. So if you drive back over an 8,000 foot mountain pass where air pressure is just over 75% of that at sea level, your 66 foot dive is now considered 1.25 x 66 feet, equals 88 feet. Now, that is just my way of reckoning. The altitude dive tables I've seen are even a bit more conservative. It's also recommended to only do two dives a day, and that safety stops are mandatory.

But there's more. I'll be driving up from Folsom, which is at just 300 feet or so. So by the time I arrive the summit, the pressure will be much lower, and my body will be off-gassing. Using the PADI pressure group system, each 1,000 feet of elevation is equivalent of two pressure groups, so at the 8000 foot summit, that'll be 16 pressure groups. So up there you're all of a sudden a PADI "P" diver and it'll take your body so and so much time to off-gas and reach equilibrium. But wait, I'll quickly be descending again to Tahoe lake level, and then it'll be perhaps an hour and a half until I actually hit the water. The PADI table would indicate that I am now a "C" diver, which is why every altitude dive should be considered a repetitive dive, even the first. It's easy to see how this can quickly become complicated, so better safe than sorry.

There's actually an additional interesting aspect: In terms of ACTUAL pressure, at our depth of 66 feet, it's really less. Instead of the weight of 66 feet of water and then a whole atmosphere of air pushing down on us, it's just the water and then 80% of what the air normally contributes, so from that perspective, the 66 foot dive is actually more like a 66 divided by 3 times 2.8 dive, or 61.6 feet. But since it is the nitrogen we're concerned about, this means nothing.

Posted by conradb212 at 11:16 PM | Comments (0)

June 29, 2007

Diving as a means for terrorism

In this day and age where we can't even take toenail clippers and a bit of toothpaste or hair gel onto an airplane for fear of its use for acts of terrorism, I suppose almost anything can be seen as a potential threat. So why not scuba diving?

This morning I saw that washingtonpost.com and other news agencies reported that the FBI has recently alerted dive shops around the country to look out for suspicious divers seeking advanced training, including night diving, diving in murky waters and pipes, advanced navigation and use of underwater vehicles. The advisory was said not to be based on a particular threat but as a routine caution. Instructors, the Post quoted, should be aware of "odd inquiries that are inconsistent with recreational diving." With NAUI estimating that there are about 1,800 dive shops around the country there are plenty of places to learn the ins and outs of diving and get the required certifications. Terrorists could then easily rent equipment, have their tanks filled and so on.

But what harm could a scuba diver do? Peruse history and you see that divers often played an important role in warfare. Terrorist fears are thus not unfounded. In WW II, Italian and British divers successfully launched devastating underwater attacks on enemy warships.

The underwater division of the Italian Navy pioneered the use of divers and mini-submarines to attack British ships stationed in Alexandria and Gibraltar in 1941. In December of 1941, the Italian submarine Scire carried three "human torpedoes." Each of those 23-feet mini subs, also nicknamed "maiale" which is Italian for "pig," (because it was about as difficult to ride and steer like a wild pig) had two divers sitting astride them like cowbows. (The picture shown is of a 1:48 scale model available from a Polish website) The design went back to World War I where the Italians had sunk the feared Austrian battleship Viribus Unitis and a freighter with a modified torpedo that was placed under the warship. The Maiale was powered by a small electric motor and carried up to 650 pounds of explosives in a detachable warhead upfront. The idea was for the two divers to get their ride through anti-submarine measures like nets and such, find their target, dive underneath it, attached the warhead like a mine to the hull of the boat, or perhaps just place it on the bottom, arm it, and then, if possible, hightail out of town. The Italians were remarkably successful with this tactic, attacking and sinking a British tanker and two battleships in the port of Alexandria, Egypt, and sinking several more during the war. (See Wiki entry on the Decima Flottiglia MAS.)

The British captured one of the Italian minisubs and copied the design and diving gear. In 1943, 51-feet long X-craft midget subs (see Wiki entry on the X class subs.), which had both diesel and electric power, tried to sink the German warship Tirpitz moored in a heavily guarded port in northern Norway. The plan was to drop charges underneath both sides of the enemy ship and then detonate them with a time-delayed fuse. That operation was only a partial success, but the Tirpitz was damaged badly enough to be out of commission for a crucial six months.

Diving history is also full of examples of divers using rebreathers to infiltrate enemy territory or perform military operations underwater. They used closed-circuit oxygen rebreathers that issued no tell-tale bubbles at all. The depth limitation of 20 to 30 feet is rarely on obstacle for such operations, and they are still being used today.

So how does all this fit into terrorism 21st century style? Well, the obvious answer is that if nail clippers and toothpaste are viewed as enough of a danger to make them illegal on airplanes, then the use of scuba equipment can represent a significant danger indeed. Terror is psychological warfare and harassment. Massive attacks like 9/11 are few and far between, but the ever-present threat impacts our lives. So it's easy to see how a few strategically executed and highly publicized attacks using scuba technology could have a devastating impact on our sport. Let's hope we won't get singled out. Terror comes in many shapes and forms and it's always better to be safe than sorry. So the FBI advisory makes sense.

Posted by conradb212 at 11:16 PM | Comments (0)

June 22, 2007

Body fat, body composition report, and diving

Yesterday I took my 11-year-old to a doctor's appointment at the Kaiser HMO facility in South Sacramento. On the way in I noticed that the Health Education room, sort of a small library with pamphlets and instructional diagrams and such, offered free body fat tests. I thought I'd stop by if the appointment didn't take too long. It didn't.

The body fat test is done by a machine. It looked like a cross between a scale and a treadmill. You stood on it, it measured your weight, and then you entered your height, age, gender, whether you were clothed or not (who wouldn't in a public facility?), and what body type you were, the choices being athletic, normal, and sedentary. You then held on to two metal handle bars so the machine could send a low intensity electrical current through the body. The process is called bioelectronic impedance and uses the different electrical resistance of different tissues, bone, muscle and fat to determine your body composition. It takes but an instant, and then you can print out the results. So what did I get?

Well, I am six foot tall, weighed 159 pounds with clothes and gym shoes, age 56, male, and I optimistically described myself as "athletic." The body comp scale printout said I had 16.9% body fat, 83.1% fat-free mass, and 64.5% total body water. It also stated that my target weight range was 144.4 to 152.1 pounds, and that my daily caloric need was 2,331 calories, based on my "moderate activity level" -- which was defined as participating in an exercise program three days a week for 20-30 minutes. I run a fairly intense course three times a week, so I felt that counted as moderate activity.

I always thought that at about 155 pounds at 6 foot I was fairly slender, and so the printout's suggested target weight of 144 to 152 surprised me. The answer to that puzzle was that I am really a "normal" body type, and not a muscular "athletic" one. According to the body composition report, athletic types have between 6 and 13% body fat, normal body types between 14 and 19%, and sedentary ones over 20%. Had I entered "normal" in response to the body type, my target weight would probably have been just around where I am.

To be honest, I was surprised that my body fat was smack in the middle of the normal range. I thought it'd be less. So I poked around a bit to see what it all means. Here is some information I found:

NOAA has body composition standards both for males and females. At a height of 6 feet, the maximum weight for a male would be 201 pounds. Maximum body fat percentage depends on age. For men under 30 it's 23%, under 40 25%, and over 40 27%. Females are allowed 33, 35, and 37%, respectively. Scuba-doc.com states that "Total body fat of less the 22% in males, and less than 28% in females is desirable" and that "trained males however average 7-10% body fat." So I am apparently not very well trained. Dr. Jolie Bookspan's "The 36 Most Common Diving Physiology Myths" is interesting reading. Bookspan conducted post-doctoral work in saturation decompression and altitude and is certainly an expert. She praises fat as a major protection against cold and also points out that women's higher body fat percentage does not necessarily mean more body fat in pounds as women are generally shorter by several inches and weigh less. Her claim: "It's not yet known whether percentage fat or absolute fat amount is more problematic to decompression issues - if either are important - another area that is still unknown, but prone to myths." However, she points out that "Fat is a slow tissue due to gas solubility. Because of high gas solubility, fat holds much nitrogen and takes time to uptake and offgas it all. This is a property of fat and is true even for fatty areas with the same degree of blood supply as leaner tissue." Activedivers.org says that "As the percentage of body fat increases, so does the risk. Fatty tissue attracts and stores nitrogen more so than other tissue types, and inhibits the off-gas process." "Diving Science by Strauss and Aksenov states that "fat tissues have five times more affinity for nitrogen than lean tissues have."

However, by and large, there really isn't a lot of truly scientific information (readily) available about how body fat affects diving. It obviously has an impact on buoyancy. It has positive properties on heat insulation. Fatter people encounter the usual prejudices, like supposed lack of fitness or problems climbing a ladder to get on board. Wetsuits and BCs generally don't come in larger sizes. Yet, I've seen a lot of fat divers, and some very prominent and accomplished ones.

So perhaps we just don't know all that much about body fat and what it means for diving. I am surprised that according to that machine, I carry 26 pounds of body fat as I certainly can't see it. Then again, I also carry about 100 pounds of water, and that thought is downright weird.

Posted by conradb212 at 11:15 PM | Comments (0)

June 19, 2007

Underwater cameras without cases

Taking pictures underwater continues to fascinate me and I wish I had more opportunity to do so. Olympus spends a lot of money on their underwater camera gear and I made a proposal to them to do a full feature on their entire lineup, sort of an informational promo piece they could use to highlight and explain their products to customers. Sadly, the proposal was circulated back and forth but nothing ever came of it.

Anyway, having had the chance to take very different kinds of cameras on dive trips, I am now convinced that picking the right camera to take with you on a dive trip is even more important than picking the right camera on a land assignment. On land, the emergence of inexpensive, powerful, yet impossibly small and slender digital cameras means you can take excellent high-res pictures anywhere. The camera never gets in the way. For serious shooting you want a digital SLR, and those are a lot larger and bulkier and that generally means a carry case for all the accessories and so on.

All of this is multiplied underwater where we're already busy and loaded down with gear. In the beginning just remembering what to do in order to stay alive pretty much takes up all discretionary time and brain cells. Later on, as we become more comfortable in this foreign environment, bringing a camera along becomes possible and lots of fun. Yet, that means picking one that's suitable for underwater photography and then the investment not only in the camera, but also its underwater case and whatever other gear it needs. That can easily meet or exceed the cost of the camera itself even with the simple deepwater cases for point & shoot compacts. Add up the needed gear for a digital SLR, and we're talking several thousands of dollars.

Apart from the cost, a camera suitably protected for underwater duty is a lot larger and bulkier. A slender compact becomes a brick, and a SLR a rather massive contraption, especially when you add the almost always necessary external flash. So a dive really becomes a dedicated photography dive. Nothing wrong with that, but maybe there is. These days we simply expect to have a small camera along wherever we go, just in case. I almost always have one in my pocket, next to my cellphone. And soon the cameras in cellphones may be good enough that even that is no longer necessary. Never count out the greed of the telcos that make it nearly impossible to simply send a picture without signing up for expensive extra services and idiotic proprietary interfaces, but it may happen.

Anyway, point is that I'd like to take a camera with me when diving without having to worry about it. No bulk, no case, no fuss. And Olympus is blazing the trail here with the awesome Stylus 770SW, the 3.5 x 2.25 x 0.75 inch 7-megapixel wonder that you can take diving without a case. I wrote about it before, marveling that you can take it way deeper than its rated 33 feet. I took it down to 67 feet in the duckweed-covered Catfish Hotel sinkhole in Florida's Manatee Springs state park. Its built-in depth meter stopped at 33 feet and the little camera protested, but kept on working. Water pressure pushed in some buttons so that functionality was a bit impaired by flashing and beeping at greater depths, but it never missed a beat and no leaks.

So last weekend Carol took another Olympus 770SW with her as she conducted checkout dives for an advanced NAUI class at the Loch Low Minn quarry in Tennessee. She wasn't very familiar with the camera yet and most of her attention was on her students as they did the deep dive part of their advanced class curriculum. The quarry is about 80 feet deep and the bottom was pretty murky with visibility down to 10-15 feet, if that. So no pretty pictures this time, but the 770 saw a depth of 77 feet. In fact, the picture above was taken with it.

How did it do? According to Carol, the buttons on this one didn't get pushed in by water pressure and all controls worked even at nearly 80 feet. What did happen was that the water pressure apparently pushed in the glass of the LCD enough to cause a black rectangle in the center of the 2.5-inch display. It disappeared as she ascended and the camera was none the worse for wear. And no leakage either. That's just amazing.

Does this mean cameras like the Olympus 770SW will replace bulky underwater cases for compacts? Maybe. If the 33-foot-rated 770 can be taken down to almost 80 feet and still work, it's probably possible to make one that can handle the recreational diving depth limit of 133 feet. And with Olympus already having taken the big step from 10 feet with their Stylus 720SW to 33 feet with the Stylus 770, I wouldn't be surprised to see the next one rated at 66 feet (which means we'd take it to 133).

Are there other issues? Yes. It can get cold down there and that may mean gloves. Carol said it was difficult to operate the tiny little buttons on the 770 SW with gloves on. Deepwater cases always have those big plastic pushbuttons that are much easier to operate with gloves. It also gets darker the deeper you go, and reading all those tiny icons and writing that already virtually impossible to decipher in bright sunlight on the surface becomes next to impossible. No problem if you really know your camera, but with a mask on and bubbles around your head and other things vying for your attention, nice large and readable labels come in handy.

Anyway, I am just thrilled with what Olympus has done with the 770 SW. But what about flash, you may ask. Built-in flashes are generally useless for anything but macro photography underwater due to "scatter," i.e. the flash illuminating all the stuff that always floats around in water instead of the subject. Well, that can be fixed by having an external flash, and Olympus just introduced the UFL-1 Underwater Strobe, rated for 133 feet. It's a slave flash which means it does not require a cable connection to the camera. Very cool, and I can't wait til I get to try one out.

Posted by conradb212 at 11:14 PM | Comments (0)

June 13, 2007

My other passion

I often bemoan the fact that I cannot go diving whenever I feel like it. Well, actually I technically can as I have a nice pool in my backyard, but that doesn't really count. It does and it doesn't. Anyway, tonight I indulged in my other passion, racing cars. So if you have no interest in cars whatsoever, this entry will not be of much value to you. To me it is a hobby and passion like scuba, something that enriches my life, gets my adrenaline pumping, and just generally makes me feel good. There are also a number of parallels to diving, and so I want to explain what it's all about, and why it is similar.

When I say racing cars, I don't mean extreme racing or anything exceedingly expensive and dangerous. For me, it's mostly just going to the local drag strip, Sacramento Raceway, and participate in the Wednesday Night "Fun Drags." What's drag racing? It's very simple. There is straight track with two lanes and it is a quarter mile long (plus another eight of a mile or so to slow down). Two cars line up and wait for the lights on the "Christmas Tree" to count down. You slowly drive up until light sensors detect the front wheels of your car. First one yellow light comes on, then a second. That means you're "staged." Then, in half second increments, three more yellow lights come on and then a green one. On green (or really a bit before, as it takes the wheels a bit of time to move past the sensors) you take off and race down the track. Whoever crosses the finish line first wins.

What's so exciting about that? Well, speed and acceleration must be primal urges or else there wouldn't be ever faster cars. Is there any rational explanation why vehicles you can buy in any showroom can go almost 200 miles per hour when the speed limit is 65 or 70? Speed thrills, apparently, and speed and power have become status symbols. But it kills, too, and that is why there are race tracks. I never race on the street. But I love to go to the track.

How did this get started? I really don't know. I've always loved cars, and I used to go to the local drag strip when I lived in upstate New York. Lebanon Valley Dragway was nestled in the woods of rural upstate, a good distance away from any civilization, and it was fun. I really didn't think I'd ever race myself, and I wouldn't, not for another 20 years.

In 2003 things didn't look so good in my life and rather than moping I made a somewhat frivolous decision. I cashed in a CD and bought a brand-new 2004 Acura RSX sports coupe, cash. I had never actually driven one other than in a Microsoft XBox video game called "Project Gotham II," but I've had Hondas before. The sales manager loved the story. A customer buying a car without even driving it, just based on a video game!

It was a nice car, all black metallic with a blueish sheen to it. I always research things, of course, and within days I became a member of ClubRSX.com, a website devoted to the car. Little did I know that this would start me on a trek where I'd become an almost instant expert, write thousands of posts, extensively modify my car, and write "FAQs" (a web notation for "Frequently Asked Questions") on electronic engine tuning and then on superchargers. Yes, within months I became obsessed with learning as much as I could about that car and how it could be modified. I got into ECU tuning, which is the science of altering the programming of a car's computer to make it adapt to modifications and to make more power. I attended a seminar by a company called Hondata that specialized in automotive computer programming, had hands-on tuning sessions, attended a performance tuning class, and spent a lot of time and money systematically modifying my car. First it was just replacing the air intake with a more efficient one, then came the exhaust header and the exhaust, the suspension, the computer, and so on and so on. I documented everything, engaged in discussion, wrote how-to's for everything I did, and soon became a source of information for others.

Eventually I got into more serious stuff. You can gain a lot of power by adding a turbo or a supercharger to a motor, and I became fascinated with superchargers. Now we're getting into something divers can relate to: compress the air and you have more oxygen molecules. More oxygen molecules mean you can burn more fuel in your engine and thus make more power. And just like there is an optimal gas mix for every depth and just as there are limits as to what you can do before things get dangerous, it's the same with internal combustion engines. They like a certain ratio between air and fuel. If it's too lean there isn't enough cooling and the engine gets hot and can blow. If it's too rich, well, then it cools okay but won't run right. It's a science.

In car tuning, there are different cliques. Some go for cool looks. Others for handling. I was drawn to speed and power. In those circles, what an engine can do on the dyno matters. How much extra power did those modifications yield? A dynamometer, or "dyno," is a machine that measures how much power a car's engine makes. That's for bragging rights. The other thing that matters is speed. Not "kills" (accounts of street races won), but actual results on the race track. You get a time slip there, and it does not lie.

It took me a while to muster up the courage to actually go race. Just like scuba, it seemed all so complicated, with all those people milling about, knowing exactly what to do, whereas to me it looked incomprehensible. So one afternoon I went, asked a lot of silly questions, and then it was time to race. Adrenaline made my heart pound as I rolled onto the track for the first time, not unlike I felt when I took my first breath underwater. Just like in the pool, I knew it was going to happen, I was going to do it, it was inevitable. I did lousy on my first run, but it was so much fun. I did much better on my second, and before the night was over, I had taken on and beaten a bewinged Nissan 300ZX that did vicious burnouts. That victory was immortalized on video by a friend. It is now on YouTube. Oh, I forgot to mention: I did not take my supercharged Acura racing that first time. I took my lowly Chrysler PT Cruiser. It has a turbo motor and is modified, too, so it is not slow.

So that started a new era in my life. I went to the track almost every Wednesday and actually won four trophies in my first season, two outright wins and two runner-ups. It was the thrill of victory and the agony of defeat, and it wasn't even very dangerous. Even a highly modified supercharged car like my Acura RSX only reached a speed of 105 to 110 miles per hour or so at the end of the quarter mile.

I became a member of the NHRA, the National Hot Rod Association, the primary sanctioning body of drag racing. Would this lead to the kind of escalation I see in scuba, where open water certification leads to advanced diving, specialties, and ever more daring and dangerous exploits? It very well can. There is almost no limit to drag racing. The fasted dragsters are fire-breathing, earth-pounding monsters with thousands of horsepowers. They run the 1/4-mile in little more than four seconds, during which they achieve speeds of over 330 miles per hour. Unthinkable you may say. But perhaps no more than Sheck Exley and Dave Shaw penetrating caves and descending to deepest depths, and technical divers ever pushing the limits of what is humanly possible.

Did it lead me there? To extremes? It didn't. I participated in a few "points races" and decided it was not for me. I loved working on my car, adding modifications, discussing them, but I felt no desire to go farther. It was a hobby that gave me pleasure and I spent a lot of time and money on it, but I felt no need to go to extremes. Will it be the same with scuba? The two are really similar in many respects. I guess I will find out.

Posted by conradb212 at 11:14 PM | Comments (0)

June 06, 2007

Missed Scuba Show 2007!

Scuba Show 2007 took place June 2nd and 3rd at the Long Beach Convention Center in the Los Angeles area. I really wanted to go. Even in this day and age of the web with its instant information delivery, trade shows are still special. You get to see and touch stuff, meet people, ask questions, collect brochures and just generally immerse yourself in the conference experience. It isn't always pretty. It costs a lot to get to a show, stay in some hotel, get to the show, find your way around, and then glean as much useful information as possible. Sometimes it's deadly. I used to attend 10 to 12 technology shows a year when I was still doing the print magazines. I have plenty of memories of getting stuck in airports, fighting with hotels who always seem to find an excuse to jack up rates because "we have several major shows in town this week." Always waiting for a cab, waiting to get in, waiting for lunch, and then waiting to get a cab or bus back to the hotel. That seems to take up much of the day. And yet, I mostly remember the good stuff. Those moments when I saw a brand-now, exciting product, met enlightened people, took copious notes and hundreds of pictures, attended (and sometimes presented at) seminars and, of course, made all the press parties. Yes, it was possible to spend an entire week in Las Vegas for, say, Comdex, and not spend a single cent on food or drink. That's what press rooms and press parties were for.

Anyway, it's been a while since I've attended a big show. These days the big 24-inch wide screen of my iMac is the show. It's Information Central where the news arrives from all over the world, in an instant; where I gather and compile data, blogs, specs and press releases; where I scan image libraries, weed out chaff, process pictures, write stories. I get as much, or more, relevant news and it's a lot cheaper this way. Traveling isn't fun anymore what with all the security check hassles at airports and all the lost luggage.

Still, I had missed DEMA in Orlando last Fall, and I really wanted to make Scuba Show 2007. Long Beach is just a six or seven hour car ride from my home in Sacramento. I knew I wouldn't have the time to go down there, leisurly attend the whole conference including seminars and parties (some day I will!), but at least drive down, take in as much of the exhibits as I could in six hours or so, then head on back, perhaps crash in a cheap roadside motel if I got tired.

I really wanted to go, but work got in the way. Several major projects needed to be finished and so it came down to the wire. I would have to leave very early in the morning Saturday to make the exhibits which were open from 10am to 6pm. Friday night came and work wasn't done, but I was close. Got up very early Saturday morning, checked email, then had to make the decision (yes, I make decisions the very last moment).

So I decided to look at the Scuba Show brochure and see who exhibited. 11 scuba gear manufacturers, but only two or three of the majors. Oceanic and Aeris were there, but not Scubapro. 19 exhibitors in underwater photo and imaging. That sounded interesting, especially since my friends at Olympus were there, and we often review their underwater gear. 14 local dive shops. 17 non-profits engaged in some sort of worthwhile diving related causes. 15 presented some sort of instruments or technical and special gear. Seven sold books, magazines or were scuba websites. Ten did apparel, from T-shirts to drysuits. Two sold dive insurance. Ten had various accessories. Another ten seemed unrelated to the industry. Now for the big one: almost 90 were travel related. That included trips, dive resorts, tourist chambers, live-aboards hotels, agents. Bottomline: Almost half of the exhibitors at Scuba Show 2007 were dive tours, hotels, or resorts. Add the local shops, and it was more than half.

A great mix, for sure, but in the end one that tipped the scale towards not going. I love dive trips and plan on going on many. I support local shops. And I most definitely love gadgets and accessories and all. But with just a very few of the actual Scuba gear manufacturers being there and showing their new stuff, I could not justify it. I know it would have been fun. I'd probably have spent most of my time at just a few booths, taken lots of pictures, picked up lots of catalogs and brochures. I'd have been awfully tempted to go on a trip and perhaps someone would have talked me into signing up for one. Or three. I probably would have spent money on some gear, bought a new mask or fins or maybe an underwater camera housing. I would have cursed myself for not allocating more time and resolved then and there to do it right next time. I'd arrive the day before. Attend seminars. Mingle, learn. See all exhibits. Attend the parties. Stay for the entire event.

So I didn't go and missed out on an adventure. Driving 12 or 14 hours to and from and seeing a show is an adventure. Our ScubaDiverInfo.com and its rapidly growing number of site visitors would have benefitted as I would have put up a major Scuba Show 2007 report. As is, there is essentially no press coverage. Four days after the show, Google News shows nothing on "Scuba Show 2007." My bad. I should have gone. It's what I do. Scoop out cool new stuff, learn about it, use it, write about it, tell others in my magazines (in the past) and on my websites.

Next time for sure. I WILL go to DEMA this year, and Scuba Show next year!

Posted by conradb212 at 11:13 PM | Comments (0)

May 21, 2007

NASA robot Zacaton sinkhole metrics... or footage?

The El Zacaton (or Xacatun) sinkhole near the coast of northeastern Mexico may well be the world's deepest sinkhole. It's where Sheck Exley lost his life in 1994. His partner Jim Bowden returned from around 900 feet. Neither had found the bottom, which had been plumbed at about 1080 feet.

Now comes interesting news. None other than NASA is using a robot named DEPTHX (which stands for Deep Phreatic Thermal Explorer) to explore El Zacaton, map the vast sinkhole and collect samples. The robot uses sonar for mapping and has an arm to grab things and bring them back to the surface. So far so good.

The whole project seems to be under the auspices of NASA's Ames Research Center, and the project is described in a March 12 article entitled "DEPTHX Robot Prepares to Explore Earths Deepest Sinkhole" on NASA's website at http://astrobiology.arc.nasa.gov/news/expandnews.cfm?id=10603. That is where it gets a bit dicey. The second paragraph of the article reads:

Zacaton is a forbidding place. It has never been fully explored, and no one knows exactly how deep it is, but estimates are that its floor lies more than 1,000 meters (well over half a mile) below the surface. A pair of SCUBA divers attempted to plumb its depths in 1994. After descending to 925 meters, one of the divers, Jim Bowden, was forced to turn back. At 925 feet, the water pressure is more than 90 times what it is at sea level. Bowdens partner, Scheck Exley, drowned in his attempt to reach the bottom.

Well. Yes, a forbidding place is certainly is, no doubt there. But that is where the accuracy ends. Does no one know how deep it is? Jim Bowden, Sheck Exley and Ann Kristovich did figure that out when they used a plumb line in April of 1993 and found a depth of over 300 meters. 329 meter or 1,080 feet, to be exact. That is over 1,000 feet, but the article on the NASA site then confuses that with 1,000 meters, which is indeed over half a mile, but also a good three times more than Zacaton actually is. Jim Bowden got down to 925 feet, not meters as stated in the article (Bowden'd be in every record book had he been to 925 METERS, and rather dead). In the next sentence it's correct: feet. But now the author claims the water pressure at 925 feet is more than 90 times that on the surface. He'd have failed PADI Open Water with that answer. Assuming Zacaton is sweetwater, the pressure at 925 feet would be more like 27 times that on the surface. And hey, Exley was not exactly unknown. Let's get his name right. It's Sheck, not Scheck.

Whew. What do we make of this? And of everyone else who simply copied the errors? Just the usual worldwide confusion over the imperial versus the metric system? Why did so many newspapers, websites, and magazines mindlessly reproduce the mistakes? Reuters goes: "El Zacaton, near the Gulf coast of northeastern Mexico, is about 100 metres (328 feet) wide and more than 1,000 metres (3,280 feet) deep. It could easily hold the Eiffel Tower" (http://www.reuters.com/article/scienceNews/idUSN1742917220070518), Six hours later, after someone must have brought it to their attention, a "corrected" version is issued, but it remains wrong: "El Zacaton, near the Gulf coast of northeastern Mexico, is about 100 metres (328 feet) wide and more than 1,000 metres (3,280 feet) deep. It could easily hold the Eiffel Tower." (http://uk.news.yahoo.com/rtrs/20070518/tsc-uk-space-jupiter-corrected-a337f0f.html). Obviously they thought they had the meters to feet conversion wrong when, in fact, they had simply copied the original error.

The Eiffel Tower should have been a dead giveaway; it is about 320 meters, and that would indeed neatly fit into Zacaton...

Most of the world's news media, including news.com, continued to have it wrong, and as of May 21, 2007, the NASA site still has it wrong also. A May 21 article by Ceci Connolly of the Washington Post has it right, and the guys at dailytech.com also caught the error, though they link to a source that includes the error.

Now I can't blame anyone in the news media for taking Reuter's word or NASA's, though a bit of fact checking never hurts. But on the NASA site itself, I really don't like to see this sort of error. I mean, in rocket science, the difference between feet and meters is pretty dramatic.

Note: Much to NASA's credit, a representative from the agency returned my email within hours, confirming the errors, and informing me that the article had been revised. The information is now correct.

Posted by conradb212 at 11:13 PM | Comments (0)

May 14, 2007

Pegasus Thruster -- Innovations in SCUBA gear

A big part of my career as a writer, editor and reviewer I have pursued for the past 15 years or so is evaluating new products, figuring out how they fit in, and what their chances for success are. Some are compelling enough to get enthusiastic about, others are incremental improvements, and quite often I found myself shaking my head and wondering, "What were they thinking?!" I must admit that every time I don my scuba gear the "What were they thinking?!" crosses my mind as I fight with some of that unwieldy, heavy equipment. True, it becomes a lot less unwieldy once in the water, but still, it's hard to believe that the current tangle of hoses and snaps and clasps is optimal, that certain aspects of the technology employed is leading instead of trailing edge, and that we aren't in store for some very significant improvement that are not only safer and more convenient, but also make us look less like a Borg out of Star Trek -- a fictitional race of ghoulish cyborgs -- and more like the sleek, stylish divers Cousteau envisioned with his initial scuba gear.

As a result, I am also intrigued to see innovation in scuba gear. I'd love to get my hands on one of those Oceanics masks that have a heads-up display showing all vital dive computer data right in front of your eyes. I was appalled at the four air hoses floating around me in my standard scuba class gear and thrilled when I found I could eliminate one by using a wireless air-integrated dive computer and another by combining the secondary air supply and the BC air hose into a single hose feeding both my BC and my Scubapro AIR2 secondary. Yes, I like innovation, and especially innovation that reduces clutter and simplifies things.

This brings me to a device I came across as I perused the annual Miami Herald Business Plan Challenge. It's the Pegasus Thruster, a novel approach to an underwater propulsion device. Underwater propulsion devices are used to cover distance quickly without exerting oneself needlessly and using up precious air. That comes in handy in cave penetration, and it can also be great fun just scooting around. Problem is that those underwater scooters are quite large. Most are barrel-type devices reminiscent of a shop-vac. They have handles and you hold onto them with both hands. Not exactly optimal when you need a hand for something else, like photography or shooting video. Well, three guys in Florida created a different kind of underwater scooter, the Pegasus Thruster.

Their idea was creating something that is light, handy, and hands-free. There were also practical considerations, like being able to operate the scooter in a variety of ways and replacing its battery while underwater. So Dean Vitale and his partners Steve Williams and Howard Sorkin came up with a sleek, elegant unit that is mounted on the back of the diver, on the air tank. The whole thing weighs just 12 pounds, roughly a third to a quarter of a scuba tank. Under water it adds maybe five pounds of negative buoyancy --- easily compensated for via an extra air bladder if so desired. The initial model just has an on/off switch that can be operated by hand, or even by the movement of your head. The little unit is supposed to propel the diver forward at a speed of three knots, which translates into about 3.5 miles per hour. That's more than a good current, and a bit faster than one normally walks on land. Not bad at all. The battery is said to last for a good hour and can be released via a locking pin. Oh, and should the propeller, already protected by wiremesh, become entangled, a safety clutch will keep it from becoming damaged. And you can take it down to 400 feet. And since it is back-mounded, there's never the danger that it kicks up silt. The picture to the left combines screen snaps from the presentation and from the Pegasus Thruster website's video. Click on it for a larger version.

A very cool idea, for sure, and a simple look at the device confirms its sleekness. A patent has been submitted, of course, #20060243188. It claims A scuba diving propulsion system comprising a propulsion apparatus comprising (a) a bracket; (b) apparatus securing said propulsion apparatus to said tank; (c) a battery mounted on said housing; (d) a motive power module mounted on said housing, and including an electric motor, a transmission operatively associated with said motor to increase the torque produced by said motor, a propeller shaft operatively associated with said transmission, and a propeller mounted on said propeller shaft.

There are some very smart details, like a torque increasing transmission, a mounting bracket system that adapts to a tank, and a general design that provides slight downward thrust so that the diver never accidentally shoots toward the surface. There are other details, like provisions to mount the device onto double tanks, or to mount two devices onto a single tank. There are safety measures like automatic cut-off should the unit overheat. And splitting the design into completely sealed modules doesn't only make sense from an underwater battery replacement point of view. It also makes sense as different parts of such a propulsion system generate and absorb different gasses. There isn't any indication as to type and technology of battery power, or how, exactly, it would be replaced underwater. Or how it handles and how you make it go this way or that since you don't hold it in your hands like a conventional scooter.

The trio submitted the Pegasus Thruster to the Miami Herald's Business Plan Challenge. 135 entries were received, 13 were chosen as finalists. The competition was lofty. These were not high school science projects. A plan to screen for adverse drug reactions, one of the leading causes of healthcare disasters, took first place. The Pegasus Thruster came in second. Wow. The Miami Herald wrote a story on the surprisingly strong showing. The trio has invested about $200,000 into the invention so far. Prototypes have been tested by marine cinematographers, the International Association of Handicapped Divers, and the Miami-Dade's Police Underwater Recovery Unit. Initial production units should become available later in 2007, for about $2,400. Though the potential market is significant -- from individuals to scuba gear rental places to professional divers -- the planned ramp-up is conservative. Maybe 20 to 50 units a month.

Hey, it's a very cool idea. The group's website has an excellent underwater demonstration video and there is another video of the trio making its business presentation at the Miami Herald. I wish the video would include a demo on how the unit is operated and how the battery is changed underwater, but that will come. One potential concern I'd have is that having an additional device on your back, and especially one with a propeller and wiremesh, may present a danger of getting caught or entangled, so a quick release is a must in my book. Else, I want one!

Posted by conradb212 at 11:12 PM | Comments (0)

May 08, 2007

Pool session

Sometimes the desire to dive just becomes overwhelming. Then it's really good to have a pool in your backyard where you at least can go under. I know, I know. It's laughable. Putting on your scuba gear just to get wet in an eight or nine foot deep pool hardly qualifies as diving, but I find it helpful nonetheless. It's certainly better than having to wait another seven weeks, or whatever, to the next dive trip. And at least to me, getting your dive gear together, putting it on, and experiencing being underwater is educational and good practice no matter when and where. Even if it is just a backyard pool.

So that's what I did last Sunday. It was a warm and sunny California day, maybe 85 degrees and the water in the pool was up to 73 or so. The pool water was clear and inviting (after the total nightmare with runoff from the hills behind my house that had left the pool a murky pond!) and just beckoned me to go in. My 11-year-old son shared the feeling and was eager to don his snorkeling gear.

Getting all my stuff together reminded me just how equipment-intense diving is. I try to keep my gear all together in a special dive bag, but even so, I had to search for my 4- and 5-pound weights, the dive computer turned up in my office where I had last uploaded its data into a notebook computer, and my dive light was missing. Not that I needed it, and I have a good idea where it is, but it was not in the dive bag. So much for keeping everything together.

My two big steel-95 compressed air tanks are in my garage, and one was still full. I knew which one was without hooking up a pressure gauge because I had paid attention in class: full cylinders have their plastic cap on, used one have it off. Carrying the steel tank up the stairs into my house and to the back painfully reminded me just how heavy and unwieldy those tanks are. One of them weighs 44 pounds. That's about as much as a wheel from a modern car, including tire. Picking one of those up and carrying it around is no fun, and few attempt it.

So finally I have everything by the pool, and run smack into the first problem. The belt that secures the tank to my Scubapro Knighthawk BC has a patented snap that needs to be adjusted for a particular tank size. They were set for the smallish 65 cu-ft cylinder I had used in Florida, and that, of course, did not fit the steel-95. Adjusting it is not obvious and the way I did it seemed to pull the velcro when I closed the snap. So I may have done it wrong.

Next problem: As usual, I have to think through how the yoke of the regulator goes onto the tank valve. And, also as usual, I wonder why aren't things designed so they only go on the proper way? As is, I can never remember if the longer part of the first stage points up or down, and so I need to make sure the hose with the regulator is on the right, the wireless transmitter that communicates with my UWATEC dive computer is on the left, and the two hoses screwed into the first stage both point slightly forward, and not backward. There.

Now it's on to the wetsuit. I didn't really need to wear it in the 70+ water for a short dive, but felt the experience wouldn't hurt. Well, guess again. Putting that very tight-fitting 7mm thing on was as big a pain as always. By the time I was done, the sides of my fingernails had dug into into the soft part of my fingertips from having to grab and pull the thick neoprene, I was sweating like a pig, and felt like sausage meat stuffed into a casing. Putting on a wetsuit is no fun. Ever.

Then I sat down and put on my dive socks that I first thought looked a bit silly, but make the dive boots go on and (and later off) much easier and also keep your feet nice and warm. I located the mask defogger, applied it and dunked the mask to wash it off. Put on my dive computer and also the funky Timex Helios Depth dive watch, just to see how it would work. Opened the tank valve, pushed the purge button on the second stage to see if I had air, checked the wireless connection between the transmitter and the computer, saw that I had just 2140 psi of air pressure in what I thought was a full 2640 psi tank (always give your dive shop time to fill the bottles so they can let them cool down, which I hadn't).

I put on the BC and am somewhat pleased that all the hooks and belts and snaps and connectors no longer seem quite as intimidating.

Then came the ever-fun task of putting on my TwinJet fins. No matter how many times I put them on, it still does not come naturally and I find myself fighting for balance until the fins are on and secured. Oh, forgot to put the snorkel onto my Frameless mask. Why they call the clip "quick-release" is not quite clear as it is anything but.

My son had been studying all this with the kind of attention you're likely to get from an 11-year-old. At times he seemed to hang on my every word of explanation, at times every bird in the background seemed more important. However, when I later quizzed him on buoyancy concepts, he had all the right answers, so apparently a kid can watch birds and listen to scuba lectures at the same time.

I make him go through a buddy check and find that I had not put the weight bags into the two pouches of the Knighthawk's integrated weight system. So we do that, I feel another 12 pounds heavier, and now it's time to go down. So I grab the scondary air supply, in my case the Knighthawk's AIR2, hold it up above my head, and push the rectangular button. I remember which of the two this way: the round button adds air to the BC, it's "round-up" or "roundup" and always reminds me what to push when I want to go up. It's hokey, but it works for me. I don't have far to go as my pool is only eight feet deep, but its FUN!!! I thoroughly enjoy breathing air through the regulator, feel the weightlessness and the serenity of the water, even in a pool.

I had brought another piece of equipment, a waterproof Pentax Optio W30 digital camera. It's a neat, sleek 7.1 megapixel camera that doesn't need a special case. Its depth-rating is ten feet and you can keep it down there for two hours. That's not as much as the 33 feet rating of the Olympus 770 SW I had tested in depths up to 70 feet in Florida, but more than good enough for snorkeling and even shallow water diving. The Optio is super-simple. It has an underwater still mode and an underwater movie mode. Once in either of those modes, you still have access to other functions, like white balance or exposure compensation or even different ways of autofocus operation. I am taking pictures of my son snorkeling and looking down, and he takes some of me diving. Later I do some movies that come out exceptionally well. It's amazing that simple 640 x 480 pixel movies from an inexpensive digital camera display great even on a 55-inch projection TV!

The night before I had tried to put my DiveOptx lenses back into my Scubapro Frameless so I could better see the readouts of my dive computer. The soft plastic lenses are supposed to be reusable. But even though I followed all instructions, I could not get them to stick. Also, it's nearly impossible to find a good place for the semi-circular plastic lenses in a modern low-volume mask. By a good place I mean one where the lenses do not obscure your vision while looking ahead and they are in the line of sight for both eyes when you look down at the computer on your wrist. I did find one, but the lenses would not stick there (not that they stuck anywhere else) due to very slightly raised lettering along the inside bottom of the mask glass. Ever since Captain Rudy from Bird's Underwater had suggested I get some "Liquid Glass" at Home Depot and glue the lenses on I had been searching for the glue. In vain. There's liquid steel, liquid wood, liquid everything, but not liquid glass. A Google search revealed that "Liquid Glass" is actually a family of car care products, so Rudy may have gotten the name wrong. I could use superglue, but I am afraid of ruining both my mask and the lenses.

It's a very bright day and so I have no problem seeing the dive computer display or even the smaller one of the Timex. The Timex officially starts a dive once it hits five feet and then it keeps track of depth and dive time, and even surface interval. Its depth reading is totally on the mark and in sync with the UWATEC. Later I found that the Timex had actually also stored depth, duration and "surface interval" of the 23 times I got above and below the 5-foot mark in the shallow pool.

While my scuba lectures had a hard time keeping my son's attention, he's totally fascinated with the bubbles that float to the surface. He follows my bubbles around and lets them pop against his mask. He does that for almost the entire 20 or 30 minute dive. We're having fun!

The chlorine in the pool does its usual thing. Though it is not excessive, my eyes burn and get red, and my nose gets stuffed up. So after showing my son how to properly purge his snorkel after a dive, I step out of my gear, hose it all off, and lay things out to dry and stow others away.

One final problem: apparently I tightened the regulator yoke knob too much as it won't budge. I am too pooped to worry about it. But the next morning I still can't get it open, even with one of those rubber sheets you use to open frozen bottle caps and jar lids. I am about ready to take a wrench to it when it occurs to me to push the purge button of the second stage. Pffffft! I thought I'd done that after I closed the tank valve, but apparently I'd opened it again. Now the yoke knob easily opens. I'd be red-faced if that happened on a dive trip. For now, I commit it to memory. Things to remember when diving, #67.

Posted by conradb212 at 11:12 PM | Comments (0)

April 22, 2007

That cool double-hose look

I must admit, I am really intrigued by the cool double-hose regulators seen in Cousteau documentaries and features. So when I came across a "retro" double-hose design, I was very tempted to buy it. I thought about it a lot, discussed it in detail, and then did some research. As usual, there is no definite answer. People like "retro," or else there would be no New Beetle, no resurrected Mini Cooper, no PT Cruiser, no new Ford Mustang, and no plans for reinvented Detroit muscle cars with that vintage look. There is usually a reason why designs change. Time moves on, new technologies replace older ones, and so on. But sometimes we stray too far off course and return to older designs in sort of a back-to-the-future way. Is that the case with the new old double-hose regulator I saw?

What am I talking about here? That would be a retro regulator made by Aqua-Lung (see picture to the left). "Aqua-lung" was the name of the original diving gear designed by Emile Gagnan and Jacques Cousteau back in 1943. Somehow, today the word, also spelled "Aqualung" and "Aqua Lung," sounds sort of antiquated and the generic term "scuba" is used instead. The famous twin-hose Aqua-lung regulators that we generally associate with Cousteau-era diving (see picture to the right) had two corrugated air tubes, one on each side of the head. One supplied air, the other was for exhaust via a one-way valve. These diaphragm-based regulators generally had a round, tin can-like housing that contained either one, two or three stages. The mouthpiece usually had one-way valves to keep air and water from going where they shouldn't.

Why the second hose? The first Aqua-lung prototypes actually only had one hose, but Cousteau found that the system began free flowing when the mouthpiece was higher than the regulator, so they fitted the second hose. That didn't completely fix the problem as air simply wants to rise, and the air in those big air hoses can pull the mouthpiece up and make it harder to breathe when the mouthpiece is lower than the regulator. The big advantage, of course, was that air bubbles emanated behind the diver's head, and not right under his nose where they interfered with photography and more easily scared fish. And without all those bubbles busting by your ears on their way up, things are quieter.

Why one, two, or three stage regulators? Well, the initial Aqua-lungs just had a single stage -- a diaphragm with a spring-loaded valve. So it was water pressure on the one side of the diaphragm and air pressure on the other. Breathing in lowered pressure and opened the valve, breathing out increased the pressure again and closed the valve before the air was vented out of holes in the can-like enclosure. It's easy to see that this arrangement only worked right at a given water pressure. Go deeper and air was wasted. Go shallower and breathing effort increased. Not so good.

So later on, Aqua-lung used 2-stage balanced designs where the first stage reduced tank pressure to an intermediate pressure of about 135 psi via a pressure-reducing valve. The second stage was a downstream diaphragm supplying air in sync with the diver's inhaling and exhaling.

As cool-looking as the two-hose design was, it had a number of disadvantages. There was the varying breathing effort depending on the position of the mouthpiece. The air-filled hoses added to buoyancy issues (though that can be minimized via hose weights). And all that air could yank the mouthpiece right out of your face when you turned into a vertical position. As a result, dual-hose designs all but disappeared around 1980. I found lots of information on old scuba equipment at www.vintagescubasupply.com and www.vintagedoublehose.com. Excellent sites, those.

Anyway, a couple of years ago, Aqua-Lung introduced a "retro" regulator, dual hoses and all. However, while it sort of looked like the originals, the new model, called "Mistral," does not have the simple elegance of the round "tin-can" dual hose regulators. With the Mistral, what you get is essentially a standard, contemporary-issue Aqua-Lung Titan first stage, largish re-breather-style hoses, and then a single-hose second stage attached to the first stage, with a small hose going from the first to the second stage. Yes, you can actually separate the second stage and put it elsewhere. The housing is new, but somehow Aqua-Lung decided not to incorporate the two stages into a cohesive unit. I've read that this was due to European regulations, though I have not seen proof of that.

How well does it work? Those who have used the new Mistral dual-hose generally seem to prefer the older, original designs such as the Phoenix Royal Aqua Master. The hoses of the retro model are described as too large and buoyant compared to the older smaller-diameter rubber hoses, though some view them, and the new mouthpiece, as an improvement. Free-flowing is still described as a problem, but users like the standard high and low pressure ports, as well as readily available service for the modern parts used in this retro Mistral. As of now, it is still on the Aqua-Lung website, but it is not listed in their 2007 catalog anymore.

So should I try to get one? There are some on eBay, and a local dive shop has one listed on its website, albeit at the very high original list price. I have no idea if I should go for it. I am tempted, though.

Posted by conradb212 at 11:11 PM | Comments (0)

April 18, 2007

Cousteau Perfection

Famed French explorer and diver Captain Jacques-Yves Cousteau, the inventor of the aqua lung, died in 1997 but a decade later his legacy seems as impressive as ever, if not more so. I realized that when I recently watched part of the often malignd Warner Home Video compilation of 12 one-hour episodes from "The Cousteau Odyssey" TV series that ran between 1977 and 1981 onto six DVDs. Before that, there was "The Undersea World of Jacques Cousteau" between 1966 and 1976 (between 1966 and 1968 called just "The World of Jacques-Yves Cousteau"), and then a number of specials on selected areas, plus "Cousteau's Rediscovery of the World" I and II between 1985 and 1994. You could say it was hard to grow up in the second part of the 20th century and not be exposed to Jacques Cousteau.

In general, anything technological filmed back in the 1960s and 1970s should look quaint by now, or perhaps otherworldly as in, in the truest sense of the word, the Apollo voyages to the moon. But not Cousteau. His productions remain totally modern, totally up-to-date. Sure, the video has some nicks and scratches, but otherwise nothing seems dated. The man was truly one-of-a-kind, one who succeeded in packaging his exploits, talents, and work into something more than the sum of the parts, something that spoke to the world in a magical way.

Case in point is "Calypso's Search for the Britannic." That dates back to 1977, but you certainly couldn't tell. The equipment all appears state-of-the-art and better. Sure, scuba experts today look at Cousteau's equipment, and smile; it has that Star Trek quality to it -- meant to imply scientific advance and professional perfection, and it was clearly designed to impress the public. Yet, unlike the Star Trek props, it actually worked. Well enough to dive the Britannic.

And it does look great. Though Cousteau helped develop the aqua lung -- scuba with a demand valve regulator as we know it today -- nothing looks like an experimental science project. It's more like science fiction. Cousteau divers wear color-coordinated wetsuits, black with elegant yellow striping. Everything fits together. Even their dry suits look good. That extends to the tanks. No bulky, battered bottles hanging off a Cousteau diver's back. No, they are integrated into a sleek black and yellow package, sort of like a high tech designer backpack. I want one! And if the air demand is too great to all fit into one of those futuristic backpacks? Well, then they resort to regular bottles, but they, too are sleek, shiny, and without a single dent or unsightly markings.

All this, of course, fits into the larger Cousteau image. There's his impressive boat, the Calypso, an ex-Royal Navy minesweeper. There's his matching seaplane, the Catalina. There's the Cousteau helicopter. And, of course, the almost cute flying saucer-shaped submersible. It's all there, that technology, all at Cousteau's disposal, and it's prominently choreographed and displayed in each episode. Calypso, Catalina, heli, submersible. This is no shoestring operation.

Then there are the subects and the presentation. By today's standards it is no high tech production, but it is masterfully thought out and crafted. The video is always just so, showing a human side and then flawless, elegant technology at its effortless best. There is a careful, perfect mix between American-English narration -- done in one of those ultra-professional, impressive, trust-inspiring voice-overs that sound like no one you ever meet in real life -- and then the French and other language conversations and interviews that lend that exotic accent without making it look like this is some translated production.

The subjects are always of almost unversal interest, and Cousteau manages to be both explorer and concerned ecologist without shrilly wagging a finger. Everyone gets their say. The sage Captain Cousteau simply and earnestly presents an issue and then lets people talk. Fishermen, workers, professors, mayors, presidents of companies. The mediterranean sea is dying, rapidly being poisoned, he says, and there are alarming images of dead sea floors where a mere 30 years ago had been teeming life. So Calypso collects water and muck samples from all over the sea, for later examination in a lab. Runoff is shown, industrial waste, nuclear power plants, acres of new hotels feeding a booming tourist industry, pollution-fueled algae eating the foundations of Venice and clogging up lakes. But then the water and muck are analyzed and it's not that bad. There must be more to it then, Cousteau offers, like landfills that deposit silt and such. It's all difficult and multi-faceted, all a matter of working together. He points out issues, but does not point fingers, is not truly upsetting anyone.

The Britannic episode was masterfully done, of course. In December of 1975, with the help of MIT-supplied side-scanning sonar they quickly find the even larger sistership of the Titanic near the island of Kea in the Aegean Sea. The episode tells its story and Cousteau attends get-togethers of survivors of its 1916 sinking while on duty as a UK rescure ship for allied woundeds. Most feel the ship had been torpedoed, a few think it had hit a mine. Captain Cousteau will go down and solve the mystery. The Britannic lies in deep water, deeper even than the Andrea Doria. 350 to 400 feet requires Trimix and careful decompression. But, as usual, the Cousteau team does it in style when they actually go down in October of 1976 (more info on the 1976 operation). There's a scale model of the Britannic and Cousteau tells the audience where his submersible will go, and the divers. The divers are equipped with all the high tech equipment they need and then some, and they are color coordinated as always. The sub provides good lighting as it accompanies the deep divers, so there's impressive video footage of the hulk of the huge vessel.

At almost 400 feet, bottom time is limited to 15 minutes and then it's up for decompression. But even that is done in style. Halfway up to the surface wait support divers and a decompression structure. The Cousteau divers simply take off their Trimix triples, neatly dock them on the chamber, then go inside. The lock is closed and the deco bell is pulled to the surface, still under pressure. While the divers sing and entertain themselves inside, a decompression expert outside adjusts the pressure until the men can exit some three hours later.

All in all, the Cousteau team did almost 70 dives to the Britannic, and the 66-year-old Cousteau goes down himself. He wears just a drysuit -- apparently the water was warm enough -- and no hood. Instead, he dons his trademark red cap. He knows the ship, of course, having carefully and scientifically studied its floorplans, but the casual way in which he is filmed entering the wreck down at almost 400 feet is still amazing. No lines. Nothing to it, really. Just science and good common sense. Just as science mandated the successful use of Trimix.

But even that's not all. For good measure, one of the Britannic survivors was located and helicoptered to the Calypso. It's 85-year-old Sheila Macbeth Mitchell who had been a nurse on the ship when it sank. That provided historic continuity, commentary by someone who'd been there, and a very human touch. The still very sharp Mitchell even gets to go down there in the submersible and sees the Britannic for herself. Then she is theatrically helicoptered off Calypso. They did all that so well.

What about the Britannic? The Captain himself finds pieces of coal where they should not be, and examines the twisted metal and pipes. The hole in the hull is much too large for a torpedo attack, he explains. Most likely the ship hit a mine, and then highly flammable coal gasses ripped the hull open.

Cousteau sure was special. A rare combination of competence, innovation, and masterful marketing and presentation. And it's all beautifully presented, poetry in word and motion, all.

Posted by conradb212 at 11:11 PM | Comments (0)

April 15, 2007

Don't eat me!

Today I bought what might be the world's funkiest dive watch. And I didn't even mean to. It was completely by chance.

I'd gone to Walmart with my son to poke around a bit. The local Walmart is one of the stops on our weekly Sunday trip that also includes the Bagel place, Walgreens, Target, the One Dollar store and others. It's a modern day father/son bonding routine, with each of us pursuing our little pleasures. At Walmart, for him it's the arcade games. For me it's looking at Blue Jeans, sunglasses and watches.

So there I am, scanning the displays with all those cheap watches, always on the lookout for one with extra-large digits so I don't have to put my reading glasses on to be able to tell the time. Yup, that's one of the pitfalls when you're north of 40, by a year or three. I see an odd looking watch with a reasonably large readout and take a closer look. Hmmm... interesting; it seems to tell not only the time, but also barometric pressure. I kneel down, put my glasses on and take a closer look. It's pretty ugly, all plasticky and with toy-like colors. It also has a huge crown and a chintzy-looking lever that, apparently, serves to lock the watch so you don't mess things up when you inadvertantly touch the crown, which from the looks of it might be often. There is no manual.

There are two others like it, or almost like it, and one has a manual. It mentions the barometric pressure reading and even a compass and a dive function. Now I am intrigued! The watch is marked down from 25 to 15 bucks and so I decide to buy it. The one with the manual in its package has strange orange accents and feels even more plasticky than the other two, but I figure I need the manual and so I take that one.

At home I take a closer look. The manual is apple-shaped and battered. The writing is tiny. Now I see that the watch is actually a TIMEX! I hadn't even noticed that. I play around with the crown and the buttons but can't find the barometric function. The instructions begin with, "If you have this manual, then you've bought one of the following HELIX watches: the ABT, DM, or WRKS (if you look at the back of your watch, you'll see that we're being honest with you.)" Not really. Mine says "HELIX Depth".

Google to the rescue. I type in "timex helix review" and the mighty search engine delivers pages of results. Among them a 2004/2005 archive from scubaboard.com. It's a discussion of the Timex Helix and it explains everything.

Seems like the Helix had been a circa 2003 Timex attempt at offering an inexpensive outdoors watch. I learned that there had been three versions. The ABT model had an altimeter and a thermometer. The WRKS had the altimeter, thermometer and a compass. And the DM "Depth" model had a thermometer and a depth gauge. Quite confusing. Apparently so much that no one knew what to make of it and Timex quickly passed the Helix inventory on to Walmart where they went for low, low prices. Word got around and cognoscenti quickly snatched them up. Why a few are now at the Walmart in Folsom, California, in the year 2007 is anyone's guess.

Anyway, the Helix Depth is quite remarkable. It's, of course, a full-function watch with time, date, second time, timer, alarm, count-down and so on, on four lines of display. There's the cool Timex Indiglo illumination. The big crown has no fewer than four positions for all sorts of settings. I learned that all from a PDF of the user manual I downloaded. The Timex website no longer has the PDF, as if the company had been so embarrassed with the Helix that it even yanked its manual. But I found it elsewhere on the web.

The manual is as funky as the watch. It's totally tongue-in-cheek, so much so that it's actually refreshing. And occasionally hokey to the max. How's "The two first positions are for more common or "serf" adjustments while the second stops are for more noble or "royal" adjustments. It's medieval modern."

Well, whatever. Turns out the Helix Depth automatically starts reading depth (down to 133 feet) and water temperature every five seconds as soon as you reach 5 feet. It also keeps track of bottom time. There is a Track and a Chrono mode. In Track mode the Helix simply displays data, and at the end of the dive maximum depth and total dive time. You can also opt to have the watch continue keeping time during a surface interval or not. Chrono mode is for when you want to separate a dive into different segments, or record multiples dives so that you can later view them. Pretty impressive.

But then it gets funky again. The manual warns that the watch is waterproof to 133 feet, but that crown and buttons not be pushed or operated while underwater. And that right after it explained which buttons to push in underwater chrono mode. Well, which is it?

The final caution, in bold, is Do not eat watch. Yes, no kidding. And the picture is right in the manual. The Timex Helix Depth was special alright.

The scubaboard folks had lots to say about it. Mostly good. Most viewed it as an inexpensive backup to a dive computer or depth gauge. Some reported it didn't really like very low temperatures, and that some parts fell off. They just glued them back on. One flooded at 110 feet, but once dried out it was fine. Pushing buttons underwater, apparently, caused no harm.

So there. Looks likeI have stumbled upon one of the oddest dive watches of all time. At some point it went for over US$100. I guess fifteen bucks is a pretty good deal for a backup depth gauge that can do a bunch more, and is a genuine Timex. I wonder what John Cameron Swayze would have thought of it.

Posted by conradb212 at 11:10 PM | Comments (0)

March 08, 2007

More on taking pictures underwater

When I had a chance last Fall to do underwater photography with a variety of different cameras, my final conclusion had been, "I wish I could go back and try again, applying what I learned." That's because the results had been mixed. There seemed a very large difference between the pictures I managed to take and the terrific underwater photography one sees in books, magazines and on websites. Now I know, of course, that whatever gets printed or displayed is always the best of the best, the one picture in a hundred, or even a thousand, that stands out. So I always need to remind myself that the people who took those great pictures also take a whole bunch of crappy ones and then they weed those out, just as I do.

Still, taking pictures underwater had been a rather humbling experience. I never fancied myself a great photographer by any means, but I am the co-founder of Digital Camera Magazine, the first magazine that exclusively covered digital photography and imaging. That seems no big deal now, but back in 1998 everyone thought we were crazy, that digital cameras were just toys, and that film would never go away or even be challenged. Well, we know how that turned out.

Anyway, in my position of running Digital Camera I've reviewed hundreds of cameras and taken tens of thousands of pictures, so I am not a novice either. But when I got into scuba and then began reviewing cameras that can shoot underwater I quickly found that taking pictures beneath the surface is different, and I wish I'd been better prepared. Which isn't easy. In my office I have hundreds of photography books. They get sent to us for review in the magazine and our photography websites. I have dozens on Photoshop and all the other imaging programs, and there are books covering every conceivable aspect of photography: landscapes, people, weddings, sports, fashion, marketing, equipment, and so on. But not a single one on underwater photography. Maybe that's just not a big enough market. But if it isn't, then why do almost all of the big camera manufacturers offer underwater housings? Still, in all my trips to Borders and Barnes & Noble book stores I have yet to find a single book on underwater photography. And believe me, those are more needed than yet another one on how to shoot models or weddings.

Anyway, I did get my wish of going back to those same places (and a few new ones), with four new cameras to test. I was determined to avoid the mistakes I had made last Fall and I was determined to return with some good shots. But most of all I as determined to get a real "feel" for how to take pictures underwater. Well, I did get to spend hours underwater and I took at least one camera with me on every dive. Was I successful? Did I do much better? Yes and no. I came back with better pictures, but what I learned, primarily, was what to do and what not to do.

See, shooting pictures above water is pretty simple. Know your camera, pick a scene, then wait for the perfect shot. Underwater it's completely different. By now I am no longer a total neebie diver and I am no longer afraid of what may await me once I go down, but it's still far from a normal environment for me. Being underwater with all that scuba gear, moving in a foreign medium, forever having to watch depth and air pressure and track all the other information on my dive computer, that's very different from standing in a field with a camera. Then there's the mask on your face, the bubbles you're blowing with every breath, and the ever-present awareness that job number one is not making some dumb mistake that could cost you your life. And, oh, let's take some pictures.

But I did learn, and here are some of the things I learned:

Picking the right camera to take with on a dive is even more important than to pick the right one above water. If you think taking along a single lens reflex camera with an external flash is a pain on a road trip, it's ten times as bad when you go diving. Underwater cases even for fairly compact dSLRs such as the Olympus Evolt E-330 are large and bulky. The external flash has its own acryllic housing. Then you need a bunch of brackets and mounting hardware and cables, and put it all together. The result is big. And heavy. And not neutrally buoyant. I quickly found that diving with a digital SLR with external flash and underwater housing is not easy at all. As a relative novice I still use my hands and arms to compensate, hold on to things and right myself. That'd be the same two arms and hands needed to hold a big SLR underwater. I hate to admit it, but at times I simply hung the whole rig over my arm, hoped that it wouldn't fall off, and used my hands to balance and swim.

That said, having a real single lens reflex camera down there opened a whole new world of picture taking. The external flash alone adds a new dimension. You really can't use an onboard flash underwater for anything but macro photography. Anything else will simply illuminate whatever debris and particles float in the water. With an external flash it all works. The farther away the flash is from the lens, the better, hence the big bracket that separates the camera from the flash by a good distance.

Those used to underwater photography with a single lens reflex would love the "live view" LCD screen on the Evolt. SLR viewfinders are terrific because they show you exactly what the lens sees, but having to peek through one underwater quickly becomes a pain. The Evolt's bright, large LCD showed what the lens sees without having to use the optical viewfinder, and that came in very handy.

However, having a big powerful camera like the Olympus Evolt exascerbates another problem I've encountered with underwater photography: that of really needing to know the camera inside out to get the best possible pictures. It's really vexing; figuring out all those buttons and levers and menus is challenging enough above the surface, but there you can often leave the camera in its automatic setting and the picturs come out just fine. Underwater, where the camera needs to work a lot harder and where using the proper settings can make all the difference, you're not only in a foreign environment with time limits and a mask on your face, but the camera is also inside this big case and it's even harder to figure out all the buttons, even if you have a reasonably good command of the camera's functions. I spent a lot of time with the manuals and thought I knew all the major functions, but once the Evolt was in its case, I decided to just set the flash to its most automatic mode (TTL auto) and the camera to its underwater setting. That worked reasonably well, but in no way exhausted all the capabilities and power of this camera.

The other extreme is to take a camera along that is so small and unobtrusive that it doesn't interfere with your diving at all. Scuba divers have had this option for years. There are inexpensive one-use film cameras that work amazingly well, and there are very compact dedicated underwater cameras, and also very compact cases for a large number of those sleek new digital cameras. However, as of now nothing I know of can beat the Olympus Stylus 770 SW, a camera that doesn't need a housing at all for a lot of dives. Its 33-foot depth rating is conservative as it works just fine at 40 to 45 feet, and even takes pictures at almost 70 feet. It never flooded even when the water pressure at 67 feet pushed in some of its mechanical buttons so that they would no longer operate reliably. The freedom this little camera provided was just terrific. Simply take it along on a dive and then shoot pictures. Or not.

Another problem I encountered was being able to read the markings and icons underwater. Things are actually magnified underwater due to the optical properties of wearing a mask, but making out those tiny icons and letters can still be a challenge. So I often found myself fiddling with settings and such when I should have used those precious minutes underwater just looking around, learning, experiencing and enjoying myself.

When I took a new camera on a dive for the first time, a Casio EX-Z750 in its dedcated deepwater case, I again found myself frustrated over not having spent enough time learning the camera and thinking things through. The Casio's case had a flash diffuser meant to minimize the dreaded "back scatter," but it didn't help very much. Even in its underwater mode, the camera insisted on setting off the flash for almost every shot, with rather mediocre results. I tried to turn the flash off just to find I couldn't. I ended up taking mostly macro shots, which turned out great, but it showed me again the one cardinal rule of underwater photography: Know your camera by heart, inside and out!

I hope that one of these days I, too, will be able to take wonderful, glorious shots of exotic sea creatures, reefs, and all the cool stuff I see in accomplished underwater photographers' galleries and websites. For now I am learning what equipment to take with me on a dive, how to prepare for it, how to handle it while I am underwater, and just generally how to take baby steps.

Posted by conradb212 at 11:10 PM | Comments (0)

February 26, 2007

More diving, finally!

It seemed like it had been forever since my last dive trip when I packed my bag for a late February trip to Northern Florida. Essentially I retraced the steps from my trip last fall, but added some new twists. In addition to just getting back underwater I wanted to learn more about caverns, learn drift diving, and do a lot more underwater photography.

By now I have read so much about caves and caverns that I am both intrigued and scared. I am also neither cave nor cavern certified (yet) and so can, legally, only get a glimpse of that special world. Fortunately, that is possible in the springs and sinks of northern Florida. There are even places where you can enter caverns with just an open water certification, such as "the cathedral" at Ginnie Springs. However, this sort of thing is not sanctioned by PADI or NAUI and so it all becomes an issue of signing waivers, knowing what you're doing, and not engaging in needless, and potentially deadly, risks. And I wasn't going to do any of that. Still, I knew that no matter what diving experience I'd have, it didn't matter. I just wanted to again feel the rush of being submerged, of floating weightlessly, of seeing and experiencing this different world that has opened to me and has been captivating me ever since I came across it. So I packed all my gear, hoped it would all make it okay, put all the essential stuff like regulator, dive computer and my cameras in a carry-on. That left very little space for clothes. Turns out, of whatever little I took, half I never even used. Divers don't need much in terms of clothes. A few pairs of socks, enough underwear (I use them under my wetsuit instead of bulky bathing suits), a pair of jeans, sneakers and a few T-shirts, is all.

Turns out all went well. My big dive bag made it to its destination and came around on the baggage carousel just as I walked up to it, fresh off the plane. Yeah. It had been opened and inspected by our friends from whatever US security agency is running our lives at airports these days, making sure we don't take little fingernail scissor and more than three ounces of toothpaste with us. Amazingly, my carry-on chuck full of electronic gear and hoses and housings and power supplies and cameras and wires and other exotic stuff was never questioned nor opened whereas my sneakers and Gateway laptop were suspiciously sniffed as potential terrorist materials.

Back at Devil's Den
Devil's Den will probably always hold a special fascination for me. It's where I began my NAUI advanced diver training for one thing, and it's a great place to dive. The setting is wild and picturesque, and though the crystal clear blue-green water of the sink itself looks so shallow, it's really not. The entrance through sheer rock and then a careful walk down a set of wooden stairs onto a platform on top of the debris cone in the center of the round surface of the sink lets you enter a wonderfully mysterious world.

Before we made it there I'd been afraid I'd have forgotten how to assemble and put on my scuba gear, but it all came back immediately. Maybe it is a bit like riding a bicycle. It was a beautiful day, sunny and warm without being too humid. My wetsuit went on a whole lot easier and even getting down all those steps in the full scuba gear seemed much less of a struggle than last Fall.

This time I'd brought along a different set of cameras, four in all, and for this first dive we chose the two very different models from Olympus. In fact, they couldn't have been any more different. The Evolt 330 digital SLR resides in a massive housing, its external flash has its own large housing, and the two are connected via a hefty, heavy metal bracket assembly that lets you twist and turn the flash any which way you want. I'd spent several hours going through the Olympus manuals, one each for each part of the vast assembly, and a few more acquainting myself with the whole setup. I concluded it'd be best to pretty much leave all settings on as automatic as possible. Once all geared up I also decided to let Carol with all her NAUI instructor expertise and experience in underwater shooting take a first crack at the Evolt (okay... she didn't have to twist my arm when she offered to carry the heavy rig down into the cavern) so that I could get used to it all again.

Me, I took along the waterproof Olympus 770 SW instead. As much attention as the massive Evolt setup in its clear acrylic housing and all its shiny buttons received each time I pulled it out and set it up, the little 770 was an even bigger attention getter whenever we unceremoniously plopped it into the water. Onlookers' reaction was always the same: they thought I'd neglectd to put the camera into its underwater housing, or simply forgotten to leave it onshore. Then it was on to explaining that this sleek little camera didn't need a housing and could, in fact, handle depths of up to 33 feet as it comes out of the box.

This time Devil's Den was fairly busy with perhaps eight to ten divers but the place is large enough for that not to be a problem. We carefully submerged the Evolt to test it for telltale bubbles that might indicate a leak. There were none. Ditto for the separate flash housing, also clear acrylic. We then did a buoyancy check on the heavy camera assembly. All hopes that it might turn out to be at least close to neutrally buoyant once in the water instantly disappeared. The thing sank like a brick. Oh well. Maybe a lighter bracket would help or a bigger housing, though it's big enough as it is.

We did a final check of our gear, made sure once again that the tanks' air valves were open, then held up the inflator and pushed the button to release air from our BCs to descend. I was surprised that there was none of the initial apprehension that I'd always felt on every dive before. I just went down, adjusted my buoyancy (I was loaded with a total of 12 pounds; a four on each front pocket and twos in the back) and began looking around. The sun shone through the cavern's small opening above and sent rays through the clear water. I saw other divers slowly appearing over the rocks, hovering in those rays and it looked just incredible. I snapped pictures of them just to find that the camera was still in above-water setting and the flash did nothing but illuminate scatter. I changed it to its proper underwater mode (the Olympus Stylus 770 SW has four - snapshot, macro, and two telephoto settings) and descended deeper. As I approached a depth of 30 feet, the camera beeped and flashed a red "depth warning" on its LCD screen. The 770 has a built-in manometer that shows depth in 1.5 foot increments. I later found that it only showed depths to 33 feet and no more.

I must admit that I had decided to take the camera deeper than its design limit of 33 feet even before the dive, wanting to see what it would do. That wasn't just reckless behavior and an attempt to see how much the camera could take before it flooded. I was confident Olympus had engineered it so there was a good safety margin and the depth limit didn't confine divers too much. So I took it deeper, all the while watching its display to make sure it was still okay. 40 feet, 45 feet and all was well. No bubbles, no flickering, no other sign of distres from the sleek little Olympus.

At this point we decided to explore some of the overhangs and venture a bit deeper under the rocks and into the nooks and crannies towards the bottom of the sink. We didn't get deeper than 40 feet last Fall, but this time I descended into a narrow cave-like descent that was indeed an overhead environment for some 30 feet or so. I had my handy magnesium LED flashlight with me. Carol motioned for my attention and reminded me to pull myself along the rocks as I had been shown before.

I never felt panicky or uneasy at all descending into the dark. At the bottom of the cave section I checked my dive computer and found, much to my delight, that we were at 51 feet. The Olympus seemed fine but when I tried to use the push button to toggle the camera into its scene selection mode to switch to the underwater macro setting it refused to do so. It also seemed like the 770 was all of a sudden in full 3X zoom mode. I took some pictures, then exited the cave section -- "cave section" is really an exaggeration; it's simply a brief overhead passage going down around the rock -- and began ascending a bit.

At about 40 feet I was able to change the camera settings again and then spent another 40 minutes or so exploring. We were shown some of the more interesting parts of the Den, including holes in the rock wall and also several sections that were either blocked off or had warning signs. I had often wondered if Devil's Den did not connect to a larger cave system as most sinks do, but I haven't found an answer yet though I asked several people. Carol, in the meantime was busy exploring the big Olympus Evolt setup and apparently had no problem at all with its size and negative buoyancy. I watched her exploring the camera and taking lots of pictures.

I marveled at all the large catfish swimming around. If any place should be called Catfish Hotel it should be Devil's Den. They are everywhere, majestically gliding around. And they are BIG. We saw "the Bus" again, the largest catfish I'd ever seen and wondered what they all eat. They are unafraid of divers, though they won't let you get close and don't generally pose for pictures.

We stayed down for almost an hour, until diving in the 70 degree water began feeling pretty cold. I wanted to go down again for one more lap around the debris cone at ten or 15 feet, but was immediately assaulted by a painful sinus headache, and so aborted the dive and came back up.

Out of the water I felt elated as I always do after dives. Walking up the steep stairs felt like nothing at all. The surface greeted us with bright sunlight and warmth, and I sat on a bench for 20 minutes or so, just basking in a wonderful feeling. My body felt great. It was a warm, satisfying glow. I felt very happy and contented. I contemplated how great diving was and how lucky I considered myself for having discovered it. Then I slowly made my way over to the park area where we had left our gear and got out of my wetsuit. The first dive of the new year had been great. We drove on to Crystal Springs to get ready for another Manatee tour early next morning.

Lenses
Oh, I should mention one other thing I learned at Devil's Den. It marked the first time I tried using Optx magnifying lenses in my Scubapro Frameless mask. I need reading glasses above water but so far had gotten by without special optics in my scuba mask. Still, while the magnifying effect underwater made it a bit easier to read the dive computer, that was only the case in good lighting conditions. When it got murky I could barely see what was on my Uwatec's smallish display. Not good. So before the trip I had finally applied the lenses I'd gotten from the Hudson dive shop in Rancho Cordova when it still existed. I followed the instructions when installing the lenses, let them dry for 48 hours and they stayed in place when I first flooded the mask. I looked down at my dive computer and, wow, I could read everything! Unfortunately, I couldn't see anything else. Everything was blurry as if my mask had gotten fogged up.

It took me a while to figure the obvious: I had the lenses on too high, way too high. So high that I could barely peek over them. I later saw pictures that showed the semi-circles of the lenses sitting squarely on top of my eyes (see above). Not a good situation, and also not very photogenic. In the evening I pried them loose and repositioned them much lower. Unfortunately, this time they did not stick. I later found someone who used the same lenses and he said I should get "liquid glass" at Home Depot and glue them down that way. I'll try that. So for the rest of the trip it was back to squinting at the dive computer.

Manatees at Crystal River
Swimming with the Manatees had been a wonderful experience last Fall and I looked forward to seeing the large, graceful, gentle creatures again. That meant getting up at 5:15AM to get to the Pier at 6:15 sharp (which to my internal West Coast clock meant three hours earlier yet). A lot of people were already there, signing waivers at the Birds Underwater dive shop, listening to the do's and don't's of interacting with the Manatees and picking out their rental gear. We had our own, of course, and it was just a matter of changing into it. I inquired about the Nitrox class that I thought I might be able to take while there, but got a feeling that wasn't going to happen. And we learned a bit more about the tragic death of a middle-aged woman the day before. She'd been on a Manatee tour, but then collapsed and died. Apparently she had been quite large, had had diabetes, high blood pressure and some other ailments. A medical doctor had been onboard and the captain of that particular boat had been none other than Bill Oestreich himself, the owner of Birds Underwater and as experienced as rescue diver as they get. She'd been attended to almost instantly and had been brought to a medical facility in record time. It didn't matter.

Kris, our boat captain from last Fall, had the day off and was not around and so this time Rudy was our captain and tour guide. It was a beautiful morning as the boat slowly made its way onto the still waters. I'd been told Rudy knew the Williston area very well and he'd be the one to ask questions about Devil's Den. I did, and Rudy volunteered a few experiences and opinions.

For photography, once I took the two Olympus cameras along to hopefully get some good Manatee shots. We were treated to some wonderful scenery, with mist rising from the water for some awesome photo ops.

As for Manatees, this time the captain didn't spend time looking for them and their telltale bubbles but headed straight for the entrance to the Three Sisters spring system. They are more plentiful in the winter and tour operators know where they hang out. Outside the springs' entrance was a "Manatee Sanctuary," an area corded off with a floating rope. There were dozens in there, and a good number were roaming around outside. We got into the water and began snorkeling and admiring the Manatees. Last time I had seen them they'd all been eating, munching on sea grass and other greenery non-stop. This time, they were tired and spent most of their time sleeping, resting at the bottom with their peculiar looking snouts seemingly buried in the silt. Every few minutes they'd come up for a brief breath, sticking just the tops of their noses out of the water. They often took two such breaths, then sank back down and continued their motionless sleep.

We headed up the entry into Three Sisters where there were more Manatees. The water wasn't quite as clear as last time and so we experimented with the big Evolt whose huge glass lens in front of the 11-22mm wide angle lens (really 22-44mm in 35mm film terminology) has a very large diameter. We thought it'd be cool to position the camera so that part of the lens was above water and part below, for a special effect. That indeed yielded interesting shots and some equally interesting phenomena. For example, the width of the divider between the underwater and the above water world depended not only on the shutter speed, but also on the movement of the water. A bit of wave action made for a big "divider" whereas a still surface made for a much narrower and more interesting one. Nothing Photoshop couldn't fix.

Eventually we swam back out of the spring system and into the main arm of the river. As I exited I saw a congregation of Manatees and decided to take a closer look. I snorkeled over without ever looking up and took some nice shots of the magnificent creatures. Noone else was around, and there was a good reason. I had inadvertently entered the Manatee Sanctuary! How embarrassing. I don't know if it's possible to be red-faced in the water. If it is, I certainly was. The captain later told me he'd seen someone inside the sanctuary and hoped it wasn't one of his group. However, I was not the only transgressor. Up in the spring system we had encountered a videographer with an IMAX camera and two very bright lights that he kept training on the Manatees. That is in strict violation of the Manatee preservation rules and caused outrage on our boat. A photographer and videographer who was there to shoot on behalf of the Manatee habitat at the Cincinnati Zoo had recorded the violation and said he was going to alert the fish and wildlife department.

Drift diving Rainbow River
In the afternoon it was on to a lesson in drift diving. Drift diving is a special skill as it requires going with the current and letting yourself "drift" down a river or other body of water. Fighting the current makes no sense and is not the objective; catching it and drifting along with it, taking in the underwater scenery and just generally having a great time is.

We had filled our tanks at Birds Underwater and loaded our gear onto the tour boat that would take us up Rainbow River. The boat itself had to be towed there. Once at the starting point, a nice county park with the somewhat odd name of K.P. Hole, we donned our scuba gear and got on the boat. Captain Rudy explained the rules and scenery. Rainbow is a five mile stretch of river starting with a spring and ending where it enters Withlacoochee River. The springs are strong, making for a 3mph current, and so the water of the entire river body is turned over several times a day. This means the water is almost always totally clear and only gets murky from human intervention. Yes, a single diver can silt up the water pretty good, as I know all too well from my own early transgressions. Rudy explained that the grass at the bottom acts as a natural filter. He said we'd see brown clumps of dirt clinging to it; all the stuff the grass removes from the water. Disturbing the grass dislodges the dirt and silts up the water.

We arrived at the drop off point and split into a diver and a snorkeler group, with the snorkelers in charge of the dive flag. I was one of the first ones off the boat and found the current surprisingly strong. So strong, in fact, that I almost missed the dock at the river shore and had to pull myself up with my hands into the calmer area behind the dock where all the divers assembled. One of the snorkelers, a fairly large older woman, entered the water for what was to be her first such snorkeling experience. She seemed apprehensive from the start and had complained about the tight fit of the wetsuit, and then quickly panicked in the strong current. She made it back to the boat and held on to it, making for some scary moments. Captain Rudy calmed her down but she decided she was not up to it. A diver from our group suddenly found that she'd lost her weights. Fortunately for her, they were found.

Then we were ready to start the estimated two-hour drift dive downriver. Down we went and I almost immediately realized I had made a big mistake: I used a brand-new mask for the first time on a long dive in an unfamiliar environment. After the Manatee tour I had found the new ScubaPro Wide Vu mask and had fallen in love with it. It fit extraordinarily well and so I had bought it at Birds Underwater. As recommended, I had used toothpaste to get off the factory-applied coating of the inside surface of the lens. I thought I'd done a good job, but the mask fogged up immediately, despite liberal use of defogger. I used spit in a last ditch attempt to keep the mask from misting, but to no avail. So down I went into this unfamiliar dive spot and unfamiliar kind of diving.

Drift diving was totally different from what I expected. I thought I'd be able to essentially see the whole river from side to side and then gently and slowly drift downstream while enjoying the scenery. Instead, I found myself almost lost in a confusing, meandering landscape of tall sea grass meadows with winding channels running through them. The water was shallow and so you had to stay close to the bottom while trying not to touch the grass. I had a hard time seeing my fellow divers, let alone the entire width of the river. The current was fairly strong, but it wasn't the kind that simply carries you along. Instead, the water pulled me so I could never just hover, but without giving me a good sense of direction or any degree of stability. I almost immediately felt lost and struggled to maintain proper buoyancy and even basic stability. Sometimes I felt close to being flipped over. What made it worse was that I could barely see through the fogged lens of my mask. I even flooded and then cleared the mask a couple of times, but it almost immediately fogged up again. So in addition to feeling rather lost and uncomfortable, I couldn't see a thing and braced myself for a rather long two hours.

Another problem I had not anticipated was the constant ear equalizing in the ever-changing depth of the river which averages about five feet. So it's up to four feet, down again to 12, up to five, down again to ten, then perhaps fifteen and back up. And so on and so on. Each new descent required new equalizing and I found I didn't enjoy that very much at all. Eventually I managed to find a bit of a rhythm in making my way through the sea grass or following one of the paths through it, but I still could see almost nothing.

Turns out Carol had similar problems with her mask, also one she had purchased just hours before. It was a Scubapro Frameless, a mask that she was very familiar with (she wears noting but), but it still leaked on her as the silicone skirt had not gotten used to her face, or developed a "face memory" as she put it. Since this was my first drift dive she insisted we swap masks. I reluctantly agreed and wearing her Frameless made a huge difference. I could finally see and began enjoying the ever-changing scenery, never knowing what would be beyond a field of sea grass and stopping to examine one of the numerous "boiling" sand areas where spring water emerged from the river bottom. You had to hold onto something to stop, and so I didn't take many pictures. My colleagues on this dive also seemed to struggle and often surfaced to regroup. My new mask fogged up on Carol as much as it had on me, plus it was too big for her face and leaked. She ended up keeping it a quarter-filled with water that she kept swirling around to keep the fogging at bay. It was clearly not a pleasant experience for her and I think we both learned a lesson.

No matter how hard I tried to elegantly hover a foot above the bottom, never stirring up silt, always being perfectly neutrally buoyant, it was hard and I mostly failed miserably. I used my hands much too often. I held on to seagrass, grabbed for whatever rocks or roots or logs I could find, and groped at and into things I felt I perhaps shouldn't. I asked myself if newcomers shouldn't wear gloves when they go drift diving. The Olympus camera, without a protective case, dangled from the carry strap around my wrist, got dragged along the sand and rocks, and bumped into stuff so much I was afraid it'd be all scratched up. It didn't, but that's one of the drawbacks of not having a tough protective case.

I had wondered how I was supposed to do a two-hour dive on a little 65 cuft tank. Supposedly that was possible because of the shallow water and little exertion required. Well, for me the exertion wasn't that little and I gulped down quite a bit of air while trying to stay on even keel and going to where I wanted to go. So I nervously kept checking my air supply and quickly realized there was no way it was going to last me two hours.

I had hoped to see some exotic wildlife or at least a turtle or two, but there was little more than the usual variety of small fish. The sole exception was a menacing looking alligator gar, a big one, with his long mean-looking snout open. Those guys have a dual row of large teeth in the upper jaw and get as long as eight to twelve feet. This one looked like a particularly sinister Barracuda and he definitely wasn't small. I wanted to take a picture... just to find that my battery had gone dead.

Eventually I found myself quite a bit ahead of the group and decided to surface when I found a boat anchor line. It turned out to be our boat, waiting for us near the starting point. I was perhaps a hundred yards ahead and waited for the rest to arrive. Rudy pointed to the other side of the river and said this was where the small cavern was. So we dived over to take a look. As always, I approached it carefully, holding on to rocks and outcroppings. It was a small cavern, but I did go inside, after Carol, and looked around. That was the end of the drift dive. It had lasted about an hour and a half, and I was down to my last 300 pounds of air or so. I was both giddy with excitement and very tired when I got out of the water and walked back to the car.

Beneath Green Pond
The final dive of the trip took me back to Manatee Springs State Park and the Catfish Hotel sink. I am still not entirely sure why they call it that as I never saw a single sizeable catfish in there. Perhaps they are in the cave system. I wouldn't know.

After that 19-year-old had died in the sink a few days before, I wondered whether the park would institute new restrictions. At Birds Underwater I had talked to a man who worked at the shop and had been at Catfish Hotel the day of the accident. I learned that it hadn't been three kids, but the one kid from Texas and then a dive master and a scuba instructor from a local dive shop not far from Crystal River. The kid had been affiliated with the dive shop and so maybe they were showing him around the local dive places. Somehow the two experienced divers ascended when they couldn't see their young buddy, assuming he'd already gone up. He hadn't. One of them went back down and entered the downstream cave system where he found the young diver, apparently wedged in somewhere, already dead. He could not get him loose and so went back up. When the body was recovered it appeared he had bumped into something hard, incurred substantial injuries, and had perhaps gotten knocked out. The sheriff was screaming at the experienced divers for letting that happen.

We got to the park somewhat late and found nothing changed. No new signs or restrictions, no mention at the ranger's station at the entrance of the park where you sign up, pay the US$10.50 fee for diving, and hand in your scuba certification card. This time we weren't alone. Several teams were diving, and not just open water divers.

We drove to the parking lot and walked over to check out the situation at sink. It was as green as last Fall, totally covered with duckweed. Duckweed is the smallest flowering plant in existence and it grows in still or slowly moving water. It's not slimy but it can sure take over. The vegetation around the sink apparently had dropped some foliage and so the sink itself somehow seemed smaller although the water level was the same. Several divers were floating by or off the entry platform. We talked to some and it quickly become obvious they were cave divers, and experienced ones at that. They wore their doubles, had stage bottles, and each had not one but two scooters. I can't remember all they'd said but apparently they'd gone in almost all the way to the end of the 10,000 feet cave system. One of them wondered how Sheck Exley had ever made it that far just swimming against the current.

We went back to the car to don our gear and passed other divers. One group returned to their truck that was parked next to us as we geared up. Once again the wetsuit practically just slid on and I was amazed (and thankful) at the huge difference a bit of humidity can make. I checked the two cameras I was going to take diving - a Casio EX-Z700 in a clear acrylic deepwater housing and, once again, the Olympus 770 SW - and then we walked back to the sink. I was first to get into the green duckweed that quickly covered everything. We took pictures of ourselves floating in duckweed, wondered how the cameras were going to handle THAT challenge, felt a bit guilty for taking the expensive Olympus Evolt setup into the mess, and worried about visibility with all those divers. I put my head underwater to take a look around and it indeed seemed darker and nowhere near as clear as last Fall when we had he sink totally to ourselves. I feared it'd be essentially a no-viz dive and that wasn't a pleasant thought.

We signaled each other and went down, with me again feeling no apprehension at all. It became immediately clear that the water was still plenty clear enough to provide a view of the entire sink in all its majesty. I lowered myself a bit to assess the situation and adjust my buoyancy. My dive buddy motioned to me and pointed behind me. Ouch. Clouds of sand and silt. Apparently I had kicked up a good bunch of silt while getting buoyancy right. I mentally slapped myself.

Then we headed for the deeper end and the dark outline of the cavern entrance. This was going to be another challenge for the Olympus. It had already handled over 50 feet at Devil's Den, but the Catfish sink was deeper yet. I approached the sloping entrance to the cavern cautiously, as usual. I clung to the bottom, always made sure I had something to hold onto, and lowered myself foot by foot beneath the dark overhang above us. Depth 63 feet. At that moment, I admit, the only thing on my mind was breaking my old "record" of 65 feet and so I improvised hand signals to my buddy indicating I wanted to go three feet deeper. She'd already motioned to go back up but then gave me the OK sign. So I carefully lowered myself another few feet and now my dive computer showed 67 feet. Somehow I was elated at that and would have gone down a bit deeper yet had my buddy not stopped her descent and started working with the big Evolt.

I laid there looking up, seeing the greenish light past the pitch-black overhang of the cavern entrance, studied the logs in the water and couldn't get enough of the view.

Then I turned my attention to my cameras and began taking pictures. It quickly became evident that the Casio, set to its sole underwater mode, used the flash no matter what and so, despite the snap-on diffuser plate in front of its internal flash, it simply lit up scatter. The Olympus, at more than twice its rated depth, was still alive, but once again it was impossible to select modes and the camera was in full telephoto mode though I hadn't extended the zoom. I studied the buttons and noticed that some seemed fully depressed. The mode button, especially, was pushed in all the way from the water pressure. I took some shots, not knowing what to expect, then alerted my buddy to the phenomenon. Though this time we both wore masks that worked for us (I had my trusted ScubaPro Frameless, she had her new Frameless that apparently now memorized her face) she looked uneasier than I remembered ever having seen her underwater and so we slowly began to ascend. There was much to see and do and we began exploring the scenery and taking pictures. As usual, the Olympus controls returned to normal operation at around 40 feet. We took close-ups of the cameras underwater, with their LCDs displaying what they saw.

On the other side of the sink, opposite of the main cavern, I noticed another, smaller cavern and swam to it to investigate. It was a dark hole and I wondered it that was the entrance to the upstream cave. That would have meant water rushing out of it and thus safety, but I decided to be extra careful and only peeked in a bit. Carol did not follow and I took that as a sign not to venture farther. I then laid on a ledge just watching the cavern. Then took some macro shots and found a few holes in the vertical limestone wall. I peeked into some and again wished I'd have a light but also understood why the park insisted on open water divers not taking one down. One of the reasons why I took it easy was that I had such a great time. The other was that I wanted to make this a one-hour-plus dive. As usual I tried to conserve air, but my little 65 cuft tank soon got dangerously low. I finally emerged after 65 minutes with less than 200 psi of pressure left.

Duckweed made the exit a riot. It was simply everywhere. So while basking in the usual mix of slight headache and afterglow we played with the stuff, took pictures and I took a bunch of breaths from Carol's Nitrox tank that still had 1200 psi in it. Though it had twice the oxygen I didn't really feel a difference, but also didn't expect to after just a half dozen breaths.

Eventually we walked up the wooden stairs and used the makeshift shower and hose to rid ourselves of as much duckweed as we could. That was no easy task as it not only gets EVERYWHERE, but also can't easily be washed off. Apparently the best way is to wash off what you can, and then wait until the rest is dry when it becomes easy to blow it off.

On the way back Carol confided she'd been cold almost right off the bat in her 3mm wetsuit and also had been very conscious of the depth limit for the 42% oxygen she had in her Nitrox tank. There are calculations that determine how deep you can go without exceeding a given maximum partial oxygen pressure, the level where oxygen toxicity might become an issue and, in a worst case scenario, lead to convulsions. The generally accepted safe number is 1.4, or a PPO2 of 1.4 - Partial Pressure Oxygen. In her case the depth limit was something like 79 feet, so we'd only gotten to ten feet of it, but she's so experienced that I felt she'd have her reasons for not wanting to go deeper.

It was getting close to five PM which was the time we had to collect our C-Cards from the Ranger Station. We got there a few minutes after and saw on the white board that two or three dive groups had still not returned. I asked the ranger if she breathed a sigh of relief every time a group came back to collect their cards and she said yes.

Later, over dinner, we all discussed our experiences. For me it was yet another instance of not encountering the expected and instead run into other issues. Given that the diving accident had preoccupied me ever since I' read about it, that I had written and talked about it, it really wasn't on my mind when we got there. Once again, I didn't feel the least bit of apprehension going down. When laying at the bottom as deep into the cavern as I dared to go, I marveled at the views and the light and putzed with the cameras. Before the dive I had been anticipating finding the exact spot where Sheck Exley had taken his picture, printed in "Caverns Measureless to Man" and duplicating it. Yet, Sheck barely entered my mind while I was down there. Even more amazingly, the fatal accident didn't either. The cavern didn't feel any more menacing, nor was I afraid. I had my usual healthy respect, but nothing more. I did not peek into the black below me and wonder what had happened to the young diver and what his last moments had been like. I did change my views on being able to get separated in the sink. If visibility is poor and one ventures into the cavern area, it's possible to lose sight of one another. But in order for that to happen, you do have to go deeper into the dark than is advisable, especially without a light.

Turns out it had been different for others. Some knew about the accident, some did not. Most seemed to simply take it as an unfortunate accident, like the death of the lady who'd died after the Manatee snorkel tour. It had been different for Carol. She told me later how she'd felt apprehension and a shiver down there near the cavern entrance, and it had not only been the cold or the fear of the approaching Nitrox depth limit. She related how divers in trouble often start doing irrational things as the situation becomes desperate. Scratch at things, drop equipment, rip off their masks or regulators. She had eerie feelings and she did not want to find some telltale mark or piece of equipment left by the young man who had died close to there just days before. A young man that had gone from the thrill of getting his Adventure Dive card to losing his life in a sink in northern Florida. I guess it's all part of it.

So there. My first dives of 2007. Every minute underwater was worth it. I thrilled in it. I screamed and laughed with joy whenever I surfaced. The equipment seemed to weigh less. My wetsuit went on easy and I never had the problem with the sides of my fingernails digging into the soft skin of my fingertips until they became infected as they had last Fall. My back, which had been acting up some before the trip, never once hurt as I feared might happen with all the heavy equipment. Not once. I'd learned to drift dive. I ran into silly new-diver mistakes and committed them all to memory so I would not make them again. I forgot only one thing, my dive log. Not a big deal as bad as my Uwatec Smart Z dive computer logs and memorizes all of my dives. I had fun and ample time with reviewing all those cameras underwater. I got to listen to other divers and exchange stories. I found I was no longer afraid right before going under. And that I enjoy scuba tremendously.

I want to go back right now.

Posted by conradb212 at 11:09 PM | Comments (0)

February 20, 2007

Another trip: testing cameras and some bad news

Tomorrow I'll be going on the first dive trip this year. Northern Florida again, visiting some of the same places I did my NAUI Advanced Diver classes and certification dives in last Fall. There will be some more training, but the primary purpose is to give four more underwater cameras a serious workout. I really look forward to this as the cameras are so different. They essentially cover the whole range from the bare minimum to innovative technology to a serious underwater rig. Each will appeal to a different potential user, and it should be interesting to see how they perform.

We'll be testing Casio's ultra-slim 5-megapixel S500, the more utilitarian Casio Z700, the brand-new Olympus 770 SW, and the Olympus Evolt digital SLR. Each has an interesting aspect. The tiny, sexy S500 doesn't even have an underwater shooting mode and it's definitely not a camera that looks like it should ever see water, but a deepwater case is available for it and so we'll see what the little thing can do. The Casio Z700 does have an underwater mode. It's a very capable 7.1 megapixel camera for which you can also get a deepwater case. So this is an example of a setup that would appeal to many tourists and recreational divers. It's small and handy, yet quite powerful, AND you can go diving with it. The third camera is nothing less than stunning. I was already impressed with the Olympus 720 SW 7.1 megapixel camera that was waterproof down to ten feet (we also tested it with its optional deepwater housing). Well, Olympus now released its successor, the 770 SW, and it can handle depths of 33 feet without housing! The final camera in the foursome, the Olympus Evolt 330 digital SLR, is an entirely different beast. It's a competent, economical single lens reflex camera with a live view LCD and an external flash. Put the camera and the flash into their respective housings, link them with the frames and brackets, and you have one huge humdinger of a rig. I can't wait to see how it handles underwater and what sort of pictures it will take.

I also came across something I didn't necessarily need to see the day before this trip. A young Texan diver died at Catfish Sink at Manatee Springs State Park, the very place I'll be going to again. The February 20, 2007 report at gainesville.com indicates that the 19-year-old got separated from his dive buddies, ran out of air, and likely drowned. His name was Bobby Rothel and he had a recent PADI Adventure Diver certification. A representative from the Sheriff's office said the three were not cave diving, "but they were diving in an area that would fall under the category of cavern diving -- where an overhead obstruction does not allow direct access to the surface." Now I've been down there. The water is crystal clear and the only way you can get separated and trapped is if you leave the sink and enter the Manatee Cave System that goes both upstream and downstream from the sink. You can't see the cave entrances either; they are to the left and right of a cavern overhang where it gets dark. Since the spring current is pretty strong it's advisable to stay clear of the syphon that can potentially suck you into the downstream cave. In order to prevent divers from venturing too far into the cavern/overhang, the park strictly forbids open water divers from taking lights with them. That would be too big of a temptation.

So what can happen? A diver without cave or cavern training and without the proper respect for potentially dangerous situations might decide to go poke around a bit deeper into the overhang. It's then pretty easy to get grabbed and swept away by the current. Without a light you'd then find yourself in pitchblack water. Panic sets in and the diver might struggle to swim against the current, thus exerting him/herself and quickly using up the air supply. Even if someone remains calm, negotiating the fairly short 500-foot cave to the basin on the other side could be deadly without light. It's not just a tube; sometimes, despite the current, you may have to grope and find the proper passage. If you don't, panic might set in and you're done. Experienced cave divers and instructors shudder at the thought of losing beginners and untrained divers that way. They know the proper procedure (don't exert yourself swimming, go to the bottom or side, grab hold of rocks and outcroppings, and pull yourself out). As is, I am glad Catfish Sink remains open, though I am sure park management at times wonder whether it's better to clearly alert to the danger or simply keep open water divers from taking lights. One could argue that a light represents a good safety device in case something happens, but the risk of it being abused for unwise exploration is likely greater.

Posted by conradb212 at 11:08 PM | Comments (0)

February 10, 2007

Some things you'd rather not know

Well, I finished a review of the late Sheck Exley's "Caverns Measureless to Man" and posted it on the site. I also informed the publisher at cavebooks.com and he was nice enough to send me a complimentary email and alert me to another must-read cave diving book, "The Darkness Beckons" by Martyn Farr. I ordered it and anticipate its arrival with great interest.

One of the things that puzzled me about Sheck Exley's story was that he never used a rebreather, or at least he never mentions one in "Caverns." Exley frequently commented on scuba bubbles dislodging debris from the cave ceiling, reducing visibility. Low viz is never pleasant, and can be life-threatening in a cave. So I wondered why Exley apparently never used a semi-closed circuit rebreather that generates far fewer bubbles, greatly reduces the amoung of gas required, provides warm and moist breathing gas, and has other benefits that reduce decompression time. I am aware that while rebreather technology has been around for well over a hundred years, they've only become commercially available (and feasible) relatively recently. However, semi-closed rebreathers had been used in cave diving as early as 1956 and 57 at the Wookey Hole Caves in Britain, and in the early 1980 they were employed in extensive and heavy-duty cave diving in France, Mexico and the US. So I began searching the web for examples where rebreathers were used in cave diving and exploration. And quickly found a stunning example.

Deepcave.com is the website of David Shaw, an Australian living in Hongkong. He was born in 1955, is a pilot and was introduced to diving by his son and was immediately hooked. They did some wreck diving, then Shaw completed a cave diving course in Florida at Cave Excursions in Live Oak, FL, and became engrossed in the thrill of it. As his explorations became more elaborate he decided to use rebreathers. He got an Inspiration unit, but soon found it couldn't handle the increasing depths he explored. So he switched to a US Navy-developed Mk15.5 and modified it for his purposes, replacing analog with digital electronics and so on. Like other cave diving enthusiasts, Shaw's primary interest was exploring what had never been explored before, but found that this took him to ever greater depths.

Shaw's site then has a section on "recent dives," those including two at Boesmansgat in South Africa in 2004. In June he went down to 718 feet. That dive is explained in a 14 page report with 30 color pictures and even a dive computer profile that is downloadable as a PDF file. Shaw described the preparations for the trip, the trip, his equipment, the modifications he had performed on it, and the dive itself in an easy, conversational style. The many pictures make the story come to life. Yes, sometimes a picture says a thousand words. Shaw describes how they found Sheck Exley's line from ten years before, 1994, during some preliminary dives. He describes how he used a program called Z-planner to compute various alternates with varying safety factors to be used with his two VR3 dive computers. He also described the setup of his rebreather that included two three liter tanks, one with air for his wing and the other with argon for his DUI dry suit. Then he had two three liter spheres, one with air and the other with oxygen -- good for a ten hour maximum. That's all he had on him. [see complete equipment list and modifications]

So then he goes on this deep dive, calmly wondering if all the equipment would stand up to the great depth. Nothing failed, however, but at about 700 feet, after a ten minute decent, Shaw experienced tunnel vision which he interpreted as the start of HPNS (High Pressure Nervous System) syndrome. He stopped and looked at the vast expanse of very clear water, commenting that breathing with his Mk15.5 rebreather was as easy as it was at 20 feet and marveled at the performance of the device. His VR3 computer then gave him all the decompression stops and he describes how he used all the tanks with different gas mixes. He also describes the technique on how to eat and drink which he did while using a reguator rather than his rebreather. He went into other practical aspects, like urinating through a valve in the drysuit. Total dive time with all the decompression stops was 517 minutes. Shaw mentioned the very low gas consumption -- barely more than a tenth of the gas used in a 1996 open-circuit scuba dive in the same location -- as one of the great advantages of the rebreather. Though this was a record depth drive with a rebreather, Shaw reported no fatigue. In fact, they did some dry cave exploring the next day, then a scooter dive at about 260 feet the day after that. Just a pleasant trip, no big deal.

Four months later, Dave Shaw returned to Boesmansgat for another world record dive (link to PDF). He explains how his digital electronics were filled with medical grade paraffin to prevent implosion at great depths. And how this time he used oxygen instead of air for the suit inflation tank, so as to have an oxygen backup. He hadn't been sure how deep bottom was and that made planning more difficult, and also presented the danger of either shooting past the line, or getting stuck in the muck if the line was too long. This time he used the dive computers just for bottom timing and carried his plans for various depths on slates. Why various plans? Because each second at a depth of over 900 feet means an extra 70 seconds of decompression.

Shaw encountered no problems whatsoever. He arrived at the bottom at 885 feet and it was nice and rocky. One of his VR3s failed but he began swimming around, saying "I was relaxed and could almost not believe where I was." Well, that was when he found a body, that of another diver by the name of Deon Dreyer, a 20-yeard-old who had died there 10 months before, on December 17, 1994. "There was no shock on my part, but rather a decision making process of what to do," goes Shaw. It was easy for him -- try to recover the body. Unfortunately, Deon's big doubles were stuck in the mud and Shaw could not dislodge him. So he did the next best thing, tie a line to the body so it could be found later. The ascent and decompression was uneventful and the whole dive lasted nine hours and 40 minutes. A body recovery was then planned for January of 1995.

So I move to the "Future Plans" section of Dave Shaw's website. There he explains the scheduled body recovery, what mixtures he'll use and how many tanks. Once again he'll have his four small on-board tanks, then a total of 19 bailout tanks in case the rebreather failed, with seven different gas mixes, with the bailouts starting to be used at 500 feet. He praises the Scubapro X650 second stage that "breathes brilliantly at great depth." He goes on to the support divers and their roles. The report completes with "More to come as I get time....." But no report.

Well, at least I had my answer. Apparently rebreathers are a workable solution for this sort of diving, one with many advantages. I contemplated that, studied the equipment list and modifications with great interest, and wondered whether Sheck Exley would eventually have started using rebreathers had he lived.

But now I wondered how the body recovery project had gone and I poked around some more and found the report at the Technical Diving Africa website. To my great dismay, not far into the page I found this statement: "This page is dedicated to David Shaw who in the attempt to retrieve Deon Dreyer lost his own life at Boesmansgat in Southern Africa."

That really hit me hard. This had seemed like such a success story. A man in his 50s calmly doing all this incredible diving, the use of the rebreathers, the total lack of any real problems. And now he apparently had died as well. What had happened?

Once again, the entire operation is described and illustrated in detail, the plan covering everything from "D-Day" minus 9 to D-day plus 2. Dave Shaw was to be the leader, doing the body recovery. Don Shirley, his backup, was going to 700+ feet in case Shaw needed help.

Then the description of the dive. Shaw goes down at 6AM, a Sony vidcam mounted on a helmet to record the recovery. Shirley follows 13 minutes later to meet him at 220 meters. Shirley sees Shaw's light, but no bubbles indicating purging during ascent and no movement. He prepares to go down, but his rebreather's Hammerhead controller implodes, likely the result of losing a bit of oil during a repair the night before. Now he's on manual rebreather control and there's no way he can go deeper. Other support divers meet Shirley 43 minutes after Shaw had begun his dive. "David not coming back," writes Shirly on a slate. Two and a half hours into the decompression Don Shirley starts feeling awful and fights for his life, feeling vertigo and throwing up -- the result of an expanding helium bubble in his inner ear. Yet, he makes it through an almost 13 hour decompression and is placed into a recompression chamber. He recovers, but it takes a long while.

Amazingly, both dead divers were recovered as well. And the Sony camera had worked, showing what had happened. Apparently the recovery had been more difficult than David Shaw expected as the body, instead of being skeletal after all those years, was in an unexpectedly buoyant condition. He is working harder than he should, building up CO2 and incurring increasing narcosis. He is alert enough to abort, but then his free-floating dive light, which he couldn't put around his neck due to the unusual vidcam helmet, gets snagged in the line tied to the dead diver. The now exhausted Shaw tries to untangle it, but can't. That was all it took.

To me, apart from being sad to find another inspiring story end in tragedy, it reaffirms a basic truth: anytime you make an exception for anything or anyone, things tend to get fouled up.

Unbelievably, you can see the entire last dive on YouTube here.

[Read detailed report of the fatal rescue mission]

Posted by conradb212 at 11:08 PM | Comments (0)

February 09, 2007

Diving safety

Pretty much ever since I took up scuba, I've been thinking of how safe it is. It's not a primary consideration, but the thought pops up and I never know when. My then ten-year-old son was quite concerned when he learned I was going to dive at Devil's Den, though I am sure it was the "devil" part that scared him and not so much the diving. The diving certification organizations, and particularly PADI, go out of their way to paint scuba diving as a perfectly safe, relaxing, and wonderful experience. Many diving books point out the exemplarily low incidence of diving accidents and deaths and compare it to numerous other activities with much higher accident rates. Even fairly scientific diving literature likes to point at diving safety and pull up numbers showing that the percentage of divers who contract the dreaded bends, decompression sickness, is extremely small. And when you look at the numbers, the sport of scuba diving indeed looks safe.

I think I read somewhere that most accidents occur in the bathroom of one's own home, but they are usually not fatal. The number of people killed in automobile accidents each year, on the other hand, is staggering, almost 50,000 every year, making up for almost half of all accidental deaths. Flying would seem to be more dangerous, but the chance of dying in an airplane crash is infinitely smaller, something like 200 a year. Unfortunately, that number is uncomfortably close to the roughly 150 people who die every year in the US from/while diving. But what does this really mean? The rate is about five deaths per million dives. So the chance is one in every 200,000 dives. Even Chuck, my PADI dive instructor with his 11,000 dives would have to go through almost 20 lifetimes of such diving until, statistically, his number is up. Last I checked, Chuck was fine. On the other hand, in February of 2007, state officials in California suspended the operations of an elite dive team after two very experienced divers with high quality equipment died during what should have been routine maintenance in the California aqueducts.

When scubadivinginfo.com was started, I set up Google alerts to send me emails with diving news, using the keyword "scuba." I have been getting them ever since, and a disconcerting number are about diving accidents from all over the world. In the beginning I occasionally reported on some of them in the news section of the website. This resulted in a bit of criticism from some who felt a scuba site should be all positive, and not point out the dark side. I thought about that for a long time. I did not want for scubadiverinfo.com to simply be a diving cheerleading site. If there are dangers, I wanted to point those out as well. In the end we decided to drop most accident reports. Not because I felt they were downers and needed to be withheld from site visitors, but because diving accidents seem to generate far more publicity than other "more common" deaths. As a result, virtually every scuba accident is reported whereas casualties in other areas of life are much less prominently featured. So putting up a news item every time I get a Google report would indeed distort things and paint a gloomy picture. Hey, statistically diving is much safer than skiing or riding a snow mobile. Yet, you rarely ever read chiding reports of skiing or snowmobile fatalities.

Maybe thinking of diving safety is simply in the nature of the sport. Almost anywhere else you can bail when things get hairy. That's not an option when you're 100 feet underwater. If you run out of air, things get desperate rather quickly. Sure, we all learn various ways to handle out-of-air situations, from "controlled ascents" to using secondary air sources from a buddy's system to buddy breathing and so on. But that assumes a diver won't panic and bolt for the surface, which in itself can have nasty consequences. Air embolisms, and all sorts of other decompression illnesses. There's just so much that can go wrong. And when it does, you're in an environment essentially foreign to man. Sure, we all begin life in a womb, in liquid, but after that we're surface dwellers and submerging means entering a hostile world.

Then there are all the various things that can go wrong. Underwater almost anything can become toxic. Life-giving oxygen? We need it, but too little and you pass out and drown. Too much and there's the danger of oxygen toxicity that leads to convulsions, and you drown. Nitrogen? An inert gas, but one that not only seeps into your system and tissues as you go deeper and thus must be carefully expelled again as you go back to the surface, but also one that becomes narcotic at depth. Nitrogen narcosis has been romantically described as "rapture of the deep" and some divers have even written about enjoying it, but it can become deadly. The minute traces of carbon monoxide in the air that hardly ever harm us on the surface? Well, increased pressure underwater means carbon monoxide partial concentration can become deadly. Carbon dioxide? That's what makes us know when we need to breathe. Get that out of whack and you can simply pass out from a lack of oxygen and drown. Not a nice picture. And that's not even going into all that can happen when you go technical and start using alternate gas mixtures.

And there's more. I generally view every sports as inherently healthy. Engaging in outdoor recreational activity means exercise, fresh air, movement, the works. Yet, the more I read, the more it seems that diving really isn't the best thing for one's health. Divers often report unusual fatigue. Those engaging in extreme diving may take days or weeks to recover from a single deep dive. Carol reports that using nitrox helps her emerge from dives much fresher and feeling much better. Yet, I've also come across rather disconcerting studies that seem to indicate that the higher partial pressure of oxygen during a dive is inherently bad for the human cardiovascular system, deteriorating its protective cell linings and resulting in other temporary and permanent damage.

I won't let any of that stop me. I intend to follow all the rules, plan my dives, never do anything stupid, and never dive beyond my training. Yet, as a curious soul I have also come across the dangers. Maybe that is just inevitable. One of the things I often think about is how no one is ever more than a few words away from absolute and total disaster, every day. Yell "fire" in a crowded theater. Or "bomb" in an airplane or airport. Tell your boss to kiss off, a teller that you're holding up the bank, or threaten a police officer. Or say certain things to a spouse, friend or relative. Life as you knew it is over in an instant. Things are simply dangerous, so why should it be any different with diving?

Posted by conradb212 at 11:07 PM | Comments (0)

February 01, 2007

More thoughts on caves

I am not claustrophobic, but I am not overly fond of dark, restricted places either. So I think the many thoughts I've been having about cave diving are triggered by the imagery I've seen in videos and pictures, that of wondrous, wide open underwater caverns, brightly lit. And probably equally appealingly by a video I saw where two cave divers used scooters to negotiate a video game-like run inside bright and very smooth underwater tubes. Up, down, left, right, it all seemed like a fun, otherworldly game.

The reality, I am certain, is quite different. And I continue to say that as someone who has no cave diving experience whatsoever. The closest thing I've ever come to it were two dives into cavern-like environments, but those did give me an idea. Then, of course, I've been reading a lot.

My early literary excursions covered a lot of wreck diving. Invariably, the experienced wreck diving teams would be joined by a cave diver, or a cave diver group wanted to try their hand at wrecks. I've previously mentioned the odd apparent rivalry between the two groups, each viewing the other with suspicion and a degree of condescension.

Wreck divers felt cave divers were cocky braggards who thought they knew everything and blindly used and trusted whatever they had learned in the caves. They criticised the use of lines inside wrecks as opposed to the wreck divers' practice of familiarizing themselves thoroughly either via blueprints, or by entering in stages, never penetrating deeper until they were thoroughly familiar with a layout. Lines, they felt, could break or, worse, ensnare divers. Likewise, they quickly termed the self-locking carabiner clips used by cave divers "suicide clips." And they had a point. In caves, there is rarely ever anything where a self-locking clip can pose a problem whereas its quick one-handed operation can come in quite handy. In wrecks, they can easily snap onto a myriad of things.

Cave divers, on the other hand, often saw wreck divers as clueless, reckless adventurers who blindly charged ahead instead of methodically planning their dives. They pointed to a lack of proper equipment and planning as opposed to their meticulous preparation. And cave divers bemoaned what they perceived as ostracism by the open water diving community in the 1960s.

As of late, I've been reading more on cave diving, and that has opened my eyes to the different mentalities.

Wreck diving can provide the thrill of discovery when locating a wreck, the thrill of identifying it if it hasn't been identified before, the prospect of finding treasure or at least retrieving artifacts, the morbid thrill of seeing the silent remnants of tragedy, the challenge of penetrating a dangerous place, and perhaps the scare of being confronted with remains.

Cave diving seems entirely different. There is the adventure of entering dark, dank places that can bring unexpected beauty, the challenge of conquering one's fears, but most of all, in the case of advanced cave divers, the prospect of going where no one has gone before. That is a challenge both to the novice who is going where s/he has not gone before, and to the advanced diver who seeks to explore "virgin" cave and mapping it out. The thrill of that seems to be the primary motivation of cave divers.

Reading Sheck Exley's "Caverns Measureless to Man" and "Taming of the Slough" both reveal numerous clues as to the nature of cave diving. Exley, for example, had a fear of heights and was prone to seasickness. He mentioned feeling uneasy in such inoccuous places as diving over the canyon-like wall of the underwater sink of Kings Bay at Crystal River, though it is only a couple dozen feet deep, and descending into "sumps" on a chair where in the darkness he pretended it was just a few feet, and not the vast distance it actually was. Or that he always felt butterflies in his stomach when he was in a restriction underwater and couldn't see.

Exley personifies the ultimate cave diver. He was both meticulous and responsible in his planning and execution, as well as the ultimate dare devil. His love of cave diving made him participate in writing rules and regulations so cave diving would not be outlawed in light of the numerous deaths. He went as far as being on the board, or chairing, not one, but several cave diving associations at the same time. He continually points out advances in safety, and is proud of the methodical development of systems and procedures that enabled safe explorations. He prioneered the "rule of thirds" where you use one third of breathing gas for penetration, then return with two thirds remaining. That gave you a third to track back, and a third reserve in case something went wrong or it took more time to find the exit. That rule was extended with the use of "staging." They'd take along additional bottles, breathe from them until they were down by a third, then drop them and either switch to the next bottle, again breathing it down to a third, before finally using the big double tanks on their backs, again breathing those down to a third before returning. That way, even at the farthest point of penetration, they'd always have 2/3rd of their gas remaining. On the way back, if all went well, they'd actually have more and more gas left. Theoretically, the main tanks would still contain a third by the time they reached the stage bottle left behind last, they'd then breathe that down to a third before reaching the next bottle, and so on.

Cave divers are also very proud of their overall contributions to the sport. Exley states that numerous improvement to scuba equipment came directly from the quest for record dives. That includes such things as forearm knives and dual valves, but also essentials like octopus regulators and buoyancy compensators. Buoyancy Compensators were invented by cave divers? I found that hard to believe, yet Carol confirmed it. I remembered Exley writing how in their early explorations they'd taken along Clorox plastic jugs and filled them with air from their regulators to provide the proper buoyancy, which is extremely important in caves. Why? Well, in open water the primary concern is not to descend or ascend too quickly, but going up and down a few feet is no big deal. In caves it's different. If you negotiate a cave only four or five feet tall, it's often essential to neither touch bottom nor ceiling as that could stir up silt and other particulates that can instantly reduce visibility to almost nothing. So proper buoyancy can be a matter of life and death.

Exley himself describes several situations where he felt he was facing death. Most came early on where he got lost, but was already experienced (and lucky) enough to find a solution and escape with his life. One was so extreme and unlikely that he conjectured it was impossible that he had survived that and perhaps he was already dead and simply did not know it. What makes him so compelling is that he seems both driven and totally cool-headed at all times. He was also a very good writer who not only managed to bring each of his dives to life but also provided insight and perspective.

"It had been an exhilarating dive, but somehow it was not enough. It never is." he wrote after they had explored an additional 1474 feet upstream into the Manatee Spring cave system to a then-record penetration distance of 3956 feet.

Exley writes that "every field of human endeavor from tiddly winks to space exploration has its champions and its marks for human endurance and achievement. Without them there would be little or no human progress, for we would have nothing to measure our efforts by or to encourage us to try harder." Yet, he's also aware that the public generally appreciates such endeavors only "as long as they are accomplished without unnecessary risk." Some things simply don't make sense. Exley was both driven to accept extreme risks, and to rationalize them and make them as safe as possible. He was aware of his mortality, repeatedly mentioning his own advancing age (even when he was just over 30 years old) or pointing to what he believed was increased susceptibility to decompression sickness once past the age of 40.

Unfortunately, cave exploration is a game with limits. Unlike the ultimate dream of every cave explorer -- that the farther he goes, the bigger the endless labyrinth gets -- reality is different. Once a cave system has been fully explored, the game is over. "The unconquerable was conquered," wrote Exley after they seemingly had explored every inch of the Manatee Spring system. "We were happy with our achievement, but we felt a sense of loss. Now there would be no future expeditions in the Manatee Springs Cave System, no renewal there of that strange yet somehow intimate companionship of divers and impossibly remote, virgin cave." (to the left is a picture we took at the entrance to the Manateee Spring caves at Catfish Hotel Sink, almost exactly at the same spot Exley took a picture, shown in "Caverns") Or, "Maybe it just goes on forever," as Exley marveled after a record penetration of 10,939 feet at Cathedral in Florida, a place he so loved that he bought the property that included the primary entrance into the system. Those words speak volumes. It's about the quest, the exploration of the unknown. Caves are finite, and thus conquerable. Just like reaching the moon is a finite goal. Mankind did it, then lost interest, settings its sights to the next goal. Mars became the next cave. Ironically, Exley had not reached the end of the Manatee Springs system. After his death, others found a side passage he had overlooked and that led to several thousands of feet beyond what he had found (Read about Jarrod Jablonski's 1994 record exploration).

Perhaps it was the finite nature of cave penetration that led Exley to seek depth records as well. "On deep dives you move into the physiological and psychological unknown, where all the components of the air you are now breathing become poisonous, where the normal problems associated with scuba diving in caves are magnified a hundredfold, where bizarre disorders arrive that medical scientists have never even dreamed of." This is where things begin to get extreme. Exley dove deeper on compressed air than most, yet there was a limit and he had to switch to various blends of trimix, something that was poorly understood at the time, for which there existed almost no decompression tables, and the investigation of which claimed the lives of some of the best cave divers.

Exley, as always, was both scientific and philosophical about it all. The secret to setting cave diving world records over a period of over 20 years and live to tell of them was what Exley termed "controlled paranoia." He always assumed that the cave was both an enemy and a friend, someone both out to get him and give him some of the greatest pleasures in his life. So he used the paranoia to meticulously think through every conceivable potential hazard and came up with solutions and backup procedures. But he used his love of caves as a means to reduce the anxiety. Once he began descending to 500 feet and beyond, it was all virgin territory. Most of the equipment simply could not take the pressure. Dive lights collapsed until they discovered it was better to pre-flood them with distilled water. Available depth gauges didn't work at all below 500 feet, and depth was measured only by the length of the line and the observed angle of the cave. Regulators proved inadequate until he settled on a Poseidon Odin. Expensive dive watches got crushed and Exley found that cheap Casio wristwatches that were merely labeled "water-resistant" to 335 feet did the job much better. Gas impurities could quickly become lethal at such pressures. Testing the various gas mixes was an issue, as was labeling the tanks so there would be no mistakes. There were reports of "vestibular hits," some lethal, when switching back from helium to a gas with more nitrogen, something Exley tackled by carefully taking alternate breaths from different bottles. The amount of gas required was enormous as a full tank lasts only a couple of minutes when exposed to pressures of almost 30 atmospheres.

His planned record dive at Nacimiento del Rio Mante required a whole new design, a wrap-around set of five tanks, plus two stage bottles snapped to the chest and four more tanks left at various depths. Descending as fast as possible was a must so as not to add to the already endless decompression time. Even for Exley, breathing became like sucking liquid through a straw. He did go down to 867 feet in just over 20 minutes, then ascended to the first of 54 decompression stops at 540 feet. All in all, the ascent took over 13 hours with all those stops.

Unfortunately, in the end these were caverns truly measureless to man, and Exley perished below 900 feet in Xacatun, a different sink hole said to be almost 1,100 feet deep and not far from Mante, on April 6, 1994 at the age of 45. A detailed accident analysis is available at http://iucrr.org/aa.htm under "Misc. Incidents."

Thinking about it, there really is a huge difference between caves and wrecks. Caves are confined spaces underground. They are age-old, often millions of years, and hardly change. Wrecks are of human origin and tragedy. They age and change. Within years they can deteriorate from almost intact vessel to a pile of rubble hardly bearing a resemblance to a ship. And all too soon they will be gone forever. The quest becomes learning as much as possible while the wreck diver can. And the challenge of an ever-changing, always dangerous environment. Cave divers have to contend with the dark, the fear of getting stuck or running out of air. Wreck divers descend through the vast waters of the ocean or a lake, and it's getting entangled that presents the challenge and danger. Cave divers, especially those in virgin territory, never quite know how deep they'll go, and how they need to negotiate deeper and shallower areas. That figures large in decompression requirements. Wreck divers have it easier that way. Go up after the predetermined time, then decompress.

Posted by conradb212 at 11:07 PM | Comments (0)

January 28, 2007

Will alligators get you?

Will alligators get you? Do they present a danger to divers? And why am I thinking about it? Well, in part because I had that experience at Catfish Sink at Manatee Springs State Park where we went in despite having spotted that alligator. The sink was relatively large and the gator wasn't close, but there were a few tense moments of decision making nonetheless. We did go in and down to the bottom of the sink at 65 feet, but the instructor kept an eye on the gator who never left the surface and didn't bother us when we ascended. The subject of the gator has come up a few times since, and we've been joking how the gator grows larger every time we tell the story or think back of it.

Well, I was reminded of that while reading the late Sheck Exley's book "Caverns Measureless to Man." In it Exley describes an excursion into a sink with an alligator. The sink's surface was considerably smaller than Catfish Sink, perhaps 80 feet diameter, and Exley describes the 8-foot alligator as staring at them arrogantly, as if conveying that he was the master of this place. He went on describing whether or not the five of them, one without any kind of wetsuit protection, should go in or not.

They decided they would, primarily based on Exley's unequivocal statement that crocodilians could not withstand pressures deeper than ten feet, and so they'd be safe from the gator below that. All went well during the dive, but Exley describes how they performed their usual ten-feet decompression stop at 15 feet instead, beyond the assumed reach of the alligator. After that they made a quick exit out of the sink. Exley added that in that year, back sometime in the 1970s, there had been seven reported alligator attacks on humans, several of them fatal. He also reported that the great majority of the attacks had been done by alligators who had been fed by humans, and thus lost their fear of them. As it turned out, the gator in that sink had, in fact, been fed by humans. Two older ladies regularly stopped by to feed "Ollie" marshmallows.

That made me think. I had previously been trying to find references on the web as to how deep alligators dive, but had found nothing. I view Exley as an expert in all things diving, and especially diving in Florida where there are a lot of gators, and so his authoritatively stated position carries weight. Still, as I plan on diving in Florida again I hoped to get some more information.

Eventually I came across a website named crocodilian.com, an Australian site run by one Dr. Adam Britton who appears to be one of the world's foremost experts on crocodilian behavior. The site provided a ton of valuable information, but, again, nothing on depth. Dr. Britton invited questions, and so I sent him this email:

Hi!

The late cave diving explorer and pioneer Sheck Exley stated in his book
"Caverns Measureless to Man" that crocodilians cannot handle pressure
below ten feet. So they decompressed deeper when alligators were
present.

How deep do crocodilians dive?

Conrad

I was pleasantly surprised to receive an email response from Dr. Britton within a day or so:

Hi Conrad,

There are reports from Lake Chamo in Ethiopia of crocodiles found below 60
feet, and I've had crocs on harpoon lines that sink to the bottom of tidal
rivers which are in excess of 10 feet deep, so Sheck Exley's statement
doesn't quite ring true. As to their maximum depth I really don't know, and
I am sure nobody else does either - virtually no work has been done in that
area, so we're relying on anecdotal observations. There are depth
monitoring devices that can be attached to transmitters, and when I get a
chance to use one I'll let you know!

Best wishes,

Adam

So there. In the light of this information, I wonder where Sheck got his information from. Obviously I can't ask him, and so we must assume that alligators can, and may, indeed dive deeper. This would be good information for divers to know. Attaching a depth monitoring device onto a crocodile or an alligator seems doable and I'd love to know the results of the data collected. As is, I'll probably judge any future alligator situations on a case-by-case basis. How many? How big? How close? Carol has been diving with gators present and says they always retreat when they see divers and I have no reason to doubt that. But knowledge backed by research is always a good thing. Oh, and for a fascination description of exploration of the Manatee Springs Cave System, click here.

Posted by conradb212 at 11:06 PM | Comments (0)

January 19, 2007

Caves and caverns

The first certification all of us earn is that of an "open water" diver. Open water? As opposed to what? Closed water? No, the "open" refers to the fact that you can go up and stick your head out of the water anytime. That's open water. Anything that's not "open water" is considered an "overhead environment." Examples of overhead environments are caves, caverns, going inside a wreck or diving under ice. When you dive in overhead environments you can't just go up if you're short on air. You first must find an exit. The implications of that are significant. And that is why diving in overhead environments requires additional training and certification.

This inevitably brings up questions. Diving in and by itself is wonderful. Breathing underwater, seeing all those sights, floating weightlessly. And the oceans are endless; it's not like you run out of things to see and experience. Why would anyone want to add to the risk by entering overhead environments that make everything more complicated and more dangerous?

Maybe it's just because the challenge is there, and people forever push the limits. Of all the dive books I've read so far, the majority deal with wreck diving and cave diving. The rest are generally introductions to scuba or textbooks on certain technical aspects, like specialized gear or diving physics. Caves and wrecks seems to be what fascinates a lot of divers, and some of the world's most famous dive sites are either wrecks or caves. Why?

I will always remember the night of my first dive in the pool, the first time I breathed underwater and we then went to the deep end of the pool. Apart from the sheer magnitude and thrill of the moment, the realization that I had done it and was breathing underwater, the one thing I remember most was how disoriented I felt. The world was essentially reduced to looking down or straight ahead and I never really knew where I was, even in the pool. At the time I attributed that to the newness of it all, and perhaps also to my black-skirted mask that did not allow glancing down or to the side. There's much discussion going on over what sort of mask is best, one that concentrates vision ahead or one that lets in as much light and vision as possible, but that's another topic. Fact is that orientation underwater, knowing where one is at all times, isn't easy, or at least it didn't come easy to me.

Even later, diving at Devil's Den in Florida, I didn't really know where I was most of the time. I know that because Carol asked me and I didn't know. And Devil's Den is a fairly confined environment. You swim around the big debris cone in the center and you can see the surface at all time. Devil's Den, of course, was new to me and when I dove there I still only had had a dozen dives or so to my name. But it also gave me my first glimpse of what an overhead environment might be like. Devil's Den isn't technically "overhead." Imagine a somewhat irregular sphere roughly halfway filled with water. There will be some places where the walls overhang. You look up and there is rock and you have to dive sideways and then up to the surface. That is still technically not even a cavern.

So what's a cavern and what's a cave? Definitions vary, but by and large a cavern is an underground area where you can still see the daylight within a certain distance and thus the exit. A cave is an overhead environment where you can't see daylight, or where daylight, and thus an exit, is so and so far away. The idea is that in caverns, you can always look around and see the exit. In caves you cannot see the exit and you must therefore know where you're going and what way is out. That is a huge difference. [The picture to the left is from the Tulum Cenote Dive Center in Mexico at cenotedive.com]

As a result, caverns and caves are treated very differently. Open water certified divers may dive in caverns, but only if accompanied by a cave-certified diver. Rules vary between agencies and locations, but all insist that anyone not trained in overhead environments have certified guidance. For cave diving, nothing other than true cave diving certification will do. There are also cavern diving courses and certifications, and they should be seen as sort of beginners classes towards "real" cave diving.

What makes cave diving so different? Different enough that rangers in certain dive sites that are mostly open water but do have caves (like the "Catfish sink" at Manatee Springs National Park in Florida) insist that you don't even take a dive light with you so as not to be tempted to go into the cave?

Well, I've never been in an underwater cave, but I've been in a few above ground. They are dark, and so you need a light. They can be narrow and constricting, and so you need to be comfortable in confined spaces. They are disorienting and you need to know the way out. And they tend to have offshoots that can easily turn them into maze-like labyrinths. Most people are somewhat intimidated by caves and some tend to panic. Now imagine being in a cave underwater where you have your dive gear on; where there are no lights on the ceiling of the cave and you need to bring your own; where there are currents and the possibility of poor visibility; and where you can run out of air. And where the cave may go deeper and you can't simply choose not to go that deep because that may be the only way through, or out. Wow.

As a result, cavern and cave training is very serious business. And the equipment used for cave diving is significantly more elaborate as well. Since you do need to see, you must bring a light along. But a light can fail. So you bring two, or better yet, three. Without air you're dead, and cave dives can be long and deep, so you bring along more air. Cave divers often use "doubles," dual tanks and a backup "pony" bottle to boot, and sometimes more. Since it is very easy to lose orientation, cave divers rely on lines. In well explored caves open as dive sites, there are permanent lines so that divers always know where to go, and which direction is out. But if a cave diver explores a new cave, running a new line and making sure it is tied off properly is a matter of life and death. And then there is the ever important visibility. Most caves have silt at the bottom, and fins can quickly stir that up to reduce visibility to almost zero. So if you lose your line and find yourself in a confined environment with zero visibility... you get the picture. What that means is that learning to fin without stirring up silt becomes a required skill.

If all this makes it sound like cave diving is dangerous, it is. A lot of people have died in caves, and not just new divers with inadequate training. So many divers died in Florida's caverns when they first became popular with sports divers in the 1970s or so that a lot of the caves were closed off and there was a real danger that all may be declared off-limits. The cave diving community realized that and, wisely, began developing procedures, training courses and materials, and required certification. Thanks to them, many of Florida's caves remain open, underground worlds that can apparently invoke thrills and bursts of adrenaline that I can only imagine at this point. Yet, even so, some caves are considered so dangerous that they were voluntarily blocked off. Even in Devil's Den I saw at least one grate that closed off an offshoot or cave entrance. Another is at the very popular Ginnie Springs.

Does that mean cave diving becomes completely safe once you have the proper training, certifications and equipment? The answer is no. It's dangerous. According to what I have read, the danger is highest to relatively inexperienced divers who go in and quickly panic. And to those who truly push the limits by exploring where no one has been before. One such maverick was Sheck Exley, the man who literally wrote the book on cave diving (several, actually). In 30 years he logged 4,000 cave dives. He was a meticulous, safety-conscious planner and perfectionist who continually and systematically advanced the state-of-the-art in a methodical -- not reckless -- manner. Yet, in the end his quest to go ever deeper cost him his life. In April of 1994, after having reached cave depths of a mind-boggling 881 feet on Trimix and other gasses, Exley went for a round number -- one thousand feet -- at Zacaton cave (a sinkhole, or "cenote," really) in Mexico. He did not come out alive (for details, click here).

What drives mankind to attempt such exploits? Is it a death wish, seeking thrills, an adrenaline rush, or pushing the state-of-the-art? What separates doable progress from reckless impossibilities? No one would, for example, shoot for being the first person to do a space walk without a suit. You can't. Diving a thousand feet deep into a cave seems almost as physically impossibly, yet somehow Exley concluded it was still within the limits of human endurance and possibility. It wasn't.

Maybe each of us has our own comfort level. Will I ever dive caves? I have no idea. Will I dive caverns? Most likely. The pictures I've seen look beautiful. Why do I even contemplate all this when I am still a total newcomer to the sport of scuba diving? Maybe for the same reason that drove me to write a detailed FAQ on superchargers for import cars before I had ever installed, tuned or even driven a supercharged vehicle -- and then have the audacity to publish it on an enthusiast website. I was ridiculed at first, but ended up its moderator and resident expert for a while. I love to learn about the more complex and extreme issues of everything I become involved in. I am a meticulate researcher and can quickly grasp concepts and sort of become an expert in any given field. I eventually did participate in the development of a supercharger for my vehicle, learned how to electronically tune it via a sophisticated computer-based engine tuning system, and then datalog everything at the racetrack. Learning theory first, then practice works for me.

I think back of being at the bottom of Catfish Sink at Manatee Springs State Park, near the entrance to the cave that connects the sink with the next open water basin about 500 feet downstream. Even just outside the siphon of the cave entry the walls were black. Carol and Ted had gone through there early on in their diving careers, just a year or two into it, duly certified for cave diving, of course. I asked her how it was inside, what one feels. She didn't tell me much. Maybe it's something one has to experience.

Posted by conradb212 at 11:05 PM | Comments (0)

January 17, 2007

Thoughts about rebreathers

A year or so before I got into scuba I saw a remarkable, though rather corny, movie that contributed to my desire to see the world underwater, and also led to another interest. The film was "The Cave," a weird combination of gorgeous diving and underwater cave photography and a B-movie horror plot of evil creatures decimating a team of divers in spite of their modern technology. One such piece of technology was a "rebreather" that enabled them to be underwater much longer. For all I knew back then, that rebreather was just fiction. Now, of course, I know that it is not. It's a scuba unit that tackles the challenge of breathing underwater in a different, and arguably more elegant, way.

Simply put, a rebreather recycles the air we breathe, taking advantage of the fact that humans only use a small fraction of the oxygen that is in every breath we take. It scrubs out the carbon dioxide and uses various mechanisms to keep things in balance. The result is a smaller scuba unit that nonetheless allows much longer bottomtime, and also makes for a far less intrusive diver because, depending on the type of rebreather, there are no bubbles, or far fewer. (The picture on the left shows a Draeger rebreather unit I saw during a dive at Lake Tahoe. Note the very small Nitrox tank.) It's easy to see how such a device can fascinate. I hate waste in any shape or form, and the rebreather wastes nothing. I am also not fond of needless work, and shlepping around far more gear than a more elegant technology allows seems nonsensical. With all those advantages, why aren't rebreathers everywhere?

That is a good question. They've actually been around far longer than conventional scuba units. Long before Cousteau and friends tested the first demand valves and the "Aqua Lung," divers had been using rebreathers. In fact, they've been used for almost 130 years. And not just in theory but in actual commercial work, going back to the end of the 19th century (in 1880, a rebreather design by Englishman Henry Fluess was successfully used to close a sluice door in a flooded tunnel). Of all the diving books I've read that touch upon rebreathers in any way, half seem to view them as some sort of specialized technology that will never be viable for sports diving. The other half see them as the future of scuba.

So why aren't we all using rebreathers? The simple answer is safety. It's not that rebreathers aren't safe if used properly, it's just that they are infinitely more complex than conventional scuba, and when it comes to the air we breathe underwater, there is no margin for error.

See, scuba, despite all the remarkable technology that goes into all those sophisticated first and second stages, is really a simple concept. Compress a lot of air into a tank, then breathe it. Sure, there are dive physics which affect how we breathe air underwater and there are physiological aspects to consider -- like the impact of nitrogen on our bodies -- but for that we have dive computers and training. But by and large, scuba is a simple process: use compressed air. It is a passive technology.

Rebreathers, on the other hand, are complex as there are many more factors to consider. Yes, you use the air you bring underwater with you much more efficiently, but that comes at a price. If the chemicals used to "scrub" the carbon dioxide out of the air fail, you can die without even noticing that anything is wrong. If something in the oxygen delivery system malfunctions you may either get too much or too little oxygen and, again, you can die. If the whole complex rebreather mechanism isn't maintained meticulously, it may fail or become contaminated, again with ominous consequences. So there. Rebreathers are an elegant technology but just about the opposite of the famous "fail-safe" ("fail-safe" meaning that when a component fails it defaults to safe). If a scuba regulator fails and starts free-flowing, you're "safe" because you continue to get air (albeit not for long); if a rebreather fails, it fails in a bad way.

So that's all bad news, but not enough to write the technology off. We humans routinely deal with dangerous technology that is safe because we made it so. If an airplane fails, the consequences are usually deadly, but we accept that risk because the technology has advanced to a point where the risk is very small. Heck, even home heating systems are essentially deadly, but we all have one. The difference is that millions use air travel and billions a heater, whereas only very few use a rebreather, hence the development of the technology is far slower.

Another issue with rebreathers is that there are different rebreather technologies. With some there are no bubbles at all. That's because with them you breathe pure oxygen and so there is no waste. The body uses part of the oxygen gas, the rest is cleansed and used again. Problem is that those can only be used in very shallow depths. Go deeper and the higher partial oxygen pressure makes oxygen toxic to our bodies and the result is a seizure. So this technology is primarily used for military purposes where the total absence of telltale bubbles is mandatory.

Most rebreathers are semi-closed, which means you do use some other gas, nitrogen. That way you can go deeper, which means pressure differences and therefore the need to be able to expell some gas. The advantage here is that oxygen and nitrogen can be combined any which way, or come from different tanks, which means the breathing gas can be mixed to the best advantage at any given depth. With less nitrogen to worry about, yet rebreathing technology that makes maximum use of oxygen, bottom times can be much longer. More complex units may add helium to the equation so that you can go deeper yet without experiencing nitrogen narcosis.

The problem is clear: how to add oxygen properly, sufficiently and reliably at all times, and how to measure its presence. So we're dealing with an inherently more complex technology that can turn deadly in an instant, one that requires extensive understanding and training and meticulous maintenance, and one that costs a whole lot more. That is the reason why rebreathers are the exception and not the norm, for now. I've only begun to learn about rebreather technology. There will undoubtedly be more entries on this topic. And I may end up using one at some point.

Posted by conradb212 at 11:05 PM | Comments (0)

January 08, 2007

Of cards

There was a time in my life where credit cards were very important to me. Maybe that's because I didn't grow up with them. We paid in cash, everything. When I moved to the United States to attend post-graduate courses at Rensselaer Polytechnic Institute in upstate New York, credit cards still weren't important. I think the first time I realized their value was when a friend from Europe visited and I had to put up a huge cash security deposit for a car rental because I did not have a credit card. So I got into the game. Department store cards came first. They had ridiculously low credit limits, and I quickly learned that paying on time was a must. One time I had a card refused at Montgomery Ward because an $8.81 balance was late.

Getting my first "real" credit cards was a revelation and soon I went on a literal collection spree, applying for everything. When I got my first real job after graduating from RPI I had an American Express card and then soon a Diner's Club card and a Carte Blanche. Yes, those two still meant something in those days. At some point I got an American Express Gold card which I was hugely proud of, especially when I visited friends in Europe where it was much more difficult to get a "gold card."

That era of credit card obsession is now ancient history. Today I view them as a pain more than anythging, as a minefield, a necessary evil. I routinely ditch the junkmail that offers yet another card, and I instinctively distrust any offer even from my own banks. I fully expect to get ripped off with obscene "late fees" or other dubious charges, and I fully expect the banks to fudge a bit so as to make me "late" so they can jack up my interest rate and report me to the credit bureaus. Yes, it's come to that. These days I almost exclusively use debit cards, drawing from money that is already mine and in my bank account. Cards are a pain, and we have far too many of them weighing down our valets.

However, there are exceptions. There are two cards that I would truly never leave home without, and those are my diver certification cards. Yes, I know it's silly, but I am more proud of my PADI Open Water Diver card and my NAUI Advanced Scuba Diver card than I ever was of any prestigious credit card. Maybe it is because I truly earned those cards, because I had to study for them, then dive underwater where humans are not supposed to be able to breathe. Maybe it's because they are tangible evidence that I succeeded at something that has become a passion of mine, diving. Maybe it's because of the signatures on those cards, the signatures of the people who opened this wondrous new world to me, enriching my life in so many ways.

I know, of course, that collecting certification cards has nothing to do with real diving experience. Despite my cards I am still of newbie scuba diver with little underwater experience, experience that I will only accumulate with the many more dives I plan on making in the years ahead. But I already know that I'll cherish each and every new C-card.

Posted by conradb212 at 11:04 PM | Comments (0)

January 03, 2007

Scuba and fitness

Recently I've thought a lot about how fit you need to be to be a scuba diver. Opinions on this vary greatly. Everyone knows and agrees that being a good tennis player or golfer takes a lot of practice. And few would dispute that athletes and ball players must work out and keep themselves in top physical condition. Things get a bit murkier with sports like auto racing. Does a NASCAR driver have to be physically fit? Some say not, but I tend to believe one must be in top physical shape to withstand the heat and g-forces and manhandling of the pedals and steering wheel over hours of racing.

But scuba? I mean, we constantly point out how wonderful it is to effortlessly float in the water, how our goal should be to expend as little energy as possible, and how nice and relaxing it is down there. During my PADI open water classes I was surprised to learn that, apparently, the average scuba diver is a male in his early 50s who is overweight and smokes. Not exactly the image of a physically fit specimen, and certainly not the image of the young, sleek, suntanned surfer-type scuba divers of both genders we see in ads and commercials.

So do scuba divers need to be fit? In their manuals and course materials, training agencies repeatedly point at fitness as a key requisite for scuba diving. We're not talking specific workouts or training programs, just general good health and a state of fitness. Smoking is a strong negative for divers not only because it affects fitness, but also because carbon monoxide from smoking has a much greater affinity to hemoglobin in our blood than oxygen. Hemoglobin carries oxygen, and that means the extra carbon monoxide in smokers' bodies reduces the amount of oxygen the blood can carry. So smoking before diving is a very bad idea.

But fitness in general? I've read books and articles claiming that scuba diving is among the least physically demanding sports of them all. Just plop in the water and float. I've seen tables that show calories burned while diving and it is supposedly nowhere near as much as for some of the rigorous physical sports out there. Even size and weight isn't that much of an issue. Sure, fat has a greater tendency to absorb nitrogen and the larger amount of nitrogen absorbed can thus play a role in decompression. However, there are a good number of fat divers who are total experts and they manage just fine.

My personal experience so far has been that fitness does matter when it comes to scuba diving, but it matters in a different way. It is absolutely true that gracefully floating underwater requires very little physical exertion. But the same is most definitely not true when it comes to carrying around equipment or gearing up. I am physically quite fit, yet hefting around scuba tanks can be demanding. Even getting up and walking the short stretch from a base camp to the water can be quite difficult. Whenever I see technical divers with dual tanks, I wonder how they ever manage out of the water. And cave divers with all their gear and even more tanks? Try that if you're not in good shape.

I cannot help but feel that the short bursts of energy required to move around in scuba gear have the potential of overwhelming an unfit, or even marginally fit, person. And given that a good percentage of the adult population suffers from chronic lower back pain, I wonder how many of those "typical" middle-aged divers incur back injuries from the equipment.

And then there are exertions one would not even think of, like donning a wetsuit. In my experience, putting on a tight-fitting 7mm wetsuit in warm weather can be equivalent to a major workout. When I put on mine, admittedly a nice and tight fit, I usually sweat bullets and breathe heavily by the time I'm all done and suited up. And unless I rest for a few minutes to catch my breath and cool down before I go under, I suck up half a tank just recovering from gearing up. When I did my NAUI advanced diver checkout dives this past Fall, I marveled at how easily Carol managed to carry and don her gear. It's because as an experienced scuba instructor she is in top shape and used to carrying all that heavy equipment. Fitness does matter.

It also matters in another way. The air in a scuba tank disappears frightfully fast. Due to the laws of physics it gets consumed faster the deeper you go, and there is nothing we can do about that. What we can do is control the rate of air consumption. Heavy breathers can empty a tank in a fraction of the time the same air lasts an experienced diver. That's in part because experienced divers will not needlessly exert themselves, but also because they have learned to control their breathing. And that, again, requires fitness. A fit person is able to return their breathing to normal much faster than an unfit one.

So as far as I am concerned, fitness matters in scuba.

Posted by conradb212 at 11:04 PM | Comments (0)

December 26, 2006

What Santa brought

Well, Santa apparently knows that I am an avid diver and reader.

I am forever searching for new diving and scuba related books. So I received "Basic Decompression - Theory and Applications" by Bruce R. Wienke, "Submerged - Adventures of America's Most Elite Underwater Archeology Team" by Daniel Lenihan, "Hiding on the Bottom - Mid Life Misadventures Down East" by James Rosemond, and "Mastering Rebreathers" by Jeffrey E. Bozanic. I also got the entire United States Navy Diving Manual on a simple unadorned CD.

And I got a very cool black Scubapro sweatshirt. It'll come in handy on my morning runs until, hopefully soon, I can wear it after dives. I also received a handy angler/diver combination tool with more functions than a Swiss army knife (I know, I was born there). And yet more diving gear: a compact and incredibly high tech-looking LED dive light. I cannot wait to go on another night dive! And I didn't know Monopoly sets came in an Underwater World Edition. Yeah! To remind me of the gator that swam above us in the Manatee Springs State Park Catfish sink, I got an alligator Christmas ornament. It arrived, well protected, in a small gear bag.

I also received another, early, Christmas present in the form of a very complimentary email from the author of one of my favorite diving books. Yes, Shadow Diver author Robert Kurson sent me the