But there generally isn't a great deal of light underwater, right? I realize it depends on how deep you go, but a lot of the most interesting stuff is going to be at the bottom of the lake/ocean.
The flash remains operational, although I suspect it will be way too anemic underwater for shots at any distance, and worse the deeper I go. As you know, the problem with underwater photography is that it's way biased toward blue (the water absorbs the reds) and good flash becomes increasingly more important the deeper you go. This housing is good to 40 meters, but it would be rare that I dive that deep, and I suspect the images would be pretty worthless anyway. I'll probably take the 630 along next trip to Mexico, but for underwater photography in the past I've always either rented a camera or rented a housing, along with a monster strobe. I've always been disappointed with underwater point-and-shoots in the past (SeaLife) and I see no reason that this 630 setup would be any different.
Anyway, I got the thing mainly for in-the-water shots and on-the-water shots, rather than under-the-water. I want to try to get some shots from the
other end of the rope.