I have hundreds and hundreds of open circuit hours shooting video in the Red Sea, on a couple of different cameras. It is absolutely second nature, almost no concious thought...
Anyway, after my switch to CCR I vowed that I wouldn't shoot any video until I felt my skills on the unit were at a point where there was a fair chance that it wouldn't kill me. One technological piece of kit is enough when it is new!
So, after 45 hours on the unit, to 52 mtrs, everything was fairly under control. Buoyancy good, skills getting pretty familiar, kit familiarity as it should be and bailout options up to speed??
At this point my best mate from the UK came out for a couple of weeks, we did some general bimbly dives, then had the chance to dive a fairly undived canyon in Ras Mohamed National Park. We didn't have a clear idea of it's exact position, but a good general idea. Definitely worth a look.
Shooting video on the unit was like it was on open circuit. Second nature. It just clicked in and off we went. Took some good shots of the eel garden on the way down, then general bottom topography while lookiing for the canyon at 45 mtrs. Then into the canyon, then down, through an overhead and round. Awesome, what an awesome place. Just me and Simon, a couple of units and a camera.
50 mtrs, down to 53, up over a small rise and down to the bottom at 52. And suddenly no inflation. What the...?
No worries, I must have knocked the dil valve. Reach back and twist, erm, that's open. Ah. Look at gauge, which read 200 bar when back at the surface...
Nil.
Oh fekk. It was at this point I wished for my bailout to have an off-board connector! But I kept it together and there was no drama, we turned the dive and headed home. Still shooting of course, just very, very careful with my buoyancy control...
Back on the boat I couldn't work out where all the dil had gone. Topped off the 3 ltr with a decanting whip and left it connected and pressurised for a couple of hours. Nothing apparently wrong, the pressure remained solid.
It was only after reviewing the footage that it became apparent where 200 bar of dil had gone.
On open circuit, which I had never realised, I exhale through my nose to keep the exhaust bubbles clear of the camera monitor screen. And yes, on descent, with the first time with the camera on CCR, I had reverted to O/C preprogrammed behaviour. Exhaling through my nose. My exhalation was clearly picked up on the camera mic.
Amongst other things that dive, lessons learned included:
1. 'New' equipment is possibly not best used for the first time to 53 mtrs.
2. Fit off-board connector to bailout.
3. Don't exhale through your nose while shooting video, and
4. Check gauges.
Subsequent video shot on CCR has been much more frugal on dil usage...
The finished video of Eel Garden Canyon, Ras Mohamed, and Thomas Canyon, Tiran, can be viewed at
Dan