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March 21, 2011

Compatibility -- the bane of underwater photographers

Only a very small percentage of the general population are scuba divers, and of those, only a relatively small part takes pictures underwater. And of that small number, only one in ten or so uses a "big rig," i.e. a digital SLR with a special housing and externally mounted strobes. When we go on dive vacations, we're usually among those, and we pay the price in terms of lugging around a lot of extra equipment and being held up by the airlines with ever larger fees for transporting all of our essentials.

Yet, the thought of going on a single dive without camera equipment and risk missing whatever there's to see down there is unthinkable and on the rare occasions where I do not take a camera on a dive, my hands feel strangely empty and I don't know what to do with them.

Going through all the trouble with the cameras is weird because I know that no matter what exotic critter I see and capture, a thousand others will already have done so, and usually better than I. Carol, on the other hand, does some outstanding underwater photography, and when I see her pictures, I feel it's all been worth it.

Anyway, as if lugging all the big gear around weren't bad enough, the manufacturers themselves seem intent on throwing as many monkey wrenches into the project as they can. True, they've finally more or less settled on SD cards for storage, so I won't have to carry around an assortment of different cards and adapters anymore, but there's still a ways to go. I am finding that out again while trying to put together a workable rig for Carol's Canon T2i dSLR.

You might wonder what the problem is, given that Canon pretty much rules supreme these days, and a good portions of the cameras I see on dive trips are now Canons. The answer is cost. If money is no object, you can simply order a full rig from one of the (actually not so) many places that specialize in underwater camera gear. But getting a housing with brackets and lights for a dSLR is expensive, quite expensive. So it would not seem unreasonable to expect photographers to mix and match and take advantage of expensive gear they already have. I mean, we're talking an industry where a single extension arm can cost hundreds of dollars, and housings can cost thousands.

Apparently it is unreasonable.

The story on trying to set things up so we could take the Rebel T2i underwater began many months ago. While every single camera ever built, no matter how similar they are, requires its own, dedicated housing, at least housings are available for the Canon T2i, a rather popular dSLR that replaced the Canon 1ti and reigned as perhaps the best buy in dSLRs until Canon quickly replaced it with the T3i. Still, housings are quite expensive and so I was thrilled to find one that was reasonable (i.e. less than twice the cost of the camera itself). So I ordered that for Carol and its delivery was expected for Christmas.

Which, of course, was optimistic as it had to be flown in from Japan. When it finally arrived, it did so without a zoom ring or lens cap. The former makes it possible to actually use the camera inside the housing, the latter keeps a very expensive lens dome from getting scratched. Not including the ring is somewhat excusable as each lens needs a different one, but one'd expect a dealer to at least ask.

Anyway, one would also expect some sort of system where expensive camera housings can be screwed onto expensive brackets using some sort of system. In computers, everyone's using the VESA mounting system that precisely describes the spacing of mounting holes and all. Well, not so with cameras. So it was off to a local machine shop to drill and thread a couple of extra holes into our Olympus bracketry.

Next, lights. We have Olympus lights and while the new housing for the Canon did not have fiber optics ports, I felt fairly confident that I could rig something up to secure the optical sensors to the housing. After a good bit or trial and error, a piece of foam did hold the fiber optics ports in place in front of the housing's flash window. But the flash did not trigger the external strobes.

So we needed to figure out how this whole fiberoptics cable system works. Simply shining a light on the sensor does not trigger the external flash, not even if you use a laser. However, another flash, even from halfway across the room, does trigger it. So it must be the brief flash that triggers the external light.

Unfortunately, the Canon uses an often annoying pre-flash to help its auto focus do its work in low light. The pre-flash can make the external flash go off, or at least it kept the external from working properly. After much searching I found how to turn the AF preflash off and the Canon's flash now did trigger the external flash. However, pictures were either greatly overblown, or it looked like the flash had not gone off at all. Email back and forth with my friend Shawn, who works at Imaging Resource, revealed that there is actually another preflash, one so close to the actual flash that the eye really cannot distinguish the two. The preflash apparently figures flash exposure and white balance, and it means it won't play ball with the Olympus flash units.


Canon's T2i replacement, the T3i, seems to have a second preflash that deals with external flash control, and in a perfect world you could simply download a program to make the T2i do that also. As is, that's not the case, and obviously we can't just ditch everything and buy yet another set of expensive camera equipment.

So how about using another way to connect the external flashes to the camera? There are what's called TTL ports on both the camera and the flash housings but, of course, they are different. Turns out that the Olympus flash has special "Olympus"-style ports whereas the housing has a "Nikonos" port, named after the old Nikonos underwater film cameras. Now there are Nikonos-to-Olympus adapter cables but they alone cost as much as a good 14-megapixel consumer camera. And since we have two external flashes, we'd need to find a 1-into-2 splitter adapter. So I checked with my friend Shawn on that. "TTL won't be possible from the T2i to the Oly flash. The TTL technologies are incompatible," he said. Sigh.

So, so far, the moral of the story is that as if underwater photography were not already expensive enough, components are also mostly incompatible, forcing you to buy new expensive lights if you don't stay with your brand and technology. That bites. It really does.

Carol's upset and wants to send the housing back. She feels we should have been told of all the various limitations, caveats and pitfalls before we were sold the goods. Me, I feel like we still may find a solution.

Stay tuned.

Posted by conradb212 at 04:48 PM | Comments (0)