ED MORRISSEY EMAILED to ask why I hadn’t posted any Cayman dive pictures. Well, I’ve done that before. But here’s something better, a dive video. I didn’t shoot this — in fact, you can see me in it with the black split fins, yellow mask, and yellow “spare air” cylinder on my chest. It was shot by Kaz Vickery of Ocean Frontiers Diving, who’s a terrific underwater videographer and who was happy to have me post a bit online. (I replaced his very nice music with Mobius Dick’s Submarine on Europa just to be sure there were no issues with the music permissions.) All of this was done in Adobe Premier Pro, and it took me about 30 minutes to put this together from the much longer video he shot.

He shoots everything in 1080i HD, but of course, that won’t matter here. If you’d like something a bit clearer than the MotionBox video below, though, you can download the video in 512kbps WMV by clicking here. This dive was on Grand Cayman’s East End, where as you can see the reefs and sealife are in excellent condition.

UPDATE: Reader Robert Ayers emails:

Thanks for the video of the Cayman diving.

As a relatively new diver (cert a year ago, 70 dives ranging from Little Cayman to Fiji) I have never even *seen* a spare air on a diver. I understand the game, but have never seen one.

You might blog sometime on your decision …

That’s a fair amount of diving in one year! Here’s the Spare Air page. It’s basically a small air tank with its own regulator, enough to let you make a leisurely ascent to the surface if your main air supply goes bad. Its main role is as wife-comforter, but if you lose a high-pressure hose or O-ring you’ve got about 45 seconds before you’re out of air from the main tank, which is enough time to get to your buddy and share air, but not a lot more. I’ve seen a high-pressure hose go for no apparent reason before, though it’s not common. I don’t know how many divers use spare air — I’ve seen a few others, and even one guy who dove with a “pony tank” (much bigger, though still smaller than a regular tank) and separate regulator as a spare. Dive equipment is quite reliable, and seldom fails catastrophically. On the other hand, the spare air gadget isn’t very expensive (you’d certainly pay more than that for air if you happened to need it!) and it’s a gadget, which as you may have noticed I’m disposed to like.

And here’s an interesting blog entry on out-of-air situations. Meanwhile, if you’re interested in diving don’t let this talk discourage you. Emergencies, especially due to equipment failure, are very rare. And as the video illustrates — though it’s a pale shadow of reality — there’s a lot of natural beauty to enjoy. Plus, as I’ve noted before, I think that diving encourages people to care about the environment.

Also, there’s more dive video — from my rebreather story for Popular Mechanics — here.