That's about the only picture you will ever see from me at 110+ below sea level.
That is at the extreme range of recreational diving. Without going into details, once you get below 100 feet on oxygen, your non-decompression diving time and your air available is extremely limited. When I took this shot, I had been down about 5 minutes... my no-decompression limit was only 8 minutes from when I took the shot, and my available air was dropping rapidly. I was diving on a high pressure aluminum 80 cylinder, and had about 12 minutes worth of air left at that depth (every 30 feet in depth doubles the amount of air you use, so I was using about 4 times the amount of air I would be using on the surface)...
Also, when you dive on air (21 percent oxygen like we have here on the surface), at 100+ feet you start suffering the effects of nitrogen narcosis... you may have heard that called the "rapture of the deep." It is like being buzzed on alcohol, and while that may sound fun to non-divers (and indeed some divers actually love to get "narked") it is can be extremely dangerous. Each person is different on how narcosis affects them, with me it takes me about twice as long to do mental tasks as it does only 30 feet higher... which actually is about normal...
When you are taking pictures while diving, you are "task loaded"... you have to monitor your own air pressure levels, your air buddy's pressure levels and mental conditions, your trim (i.e. making sure you are horizontal so you are not damaging the reef or your gear), the current and/or surge that is going on, your non-decompression time remaining, and on top of all that you have to do all the photography stuff like focus, composition, lighting and exposure in a camera entirely encased in plastic... while maintaining buoyancy floating just a foot or so away from your subject...
At depth, when hit by nitrogen narcosis, it gets tricky.
Screwing up while diving at 110 feet doesn't mean you get a bad picture, it means you end up with a bad case of the bends, an air embolism or you die.
Most of my shots are taken in the top 50 feet of the water column, not only because most of the corals and fish are better there... and not only because the seawater hasn't filtered out all of the colors except blue like it has when deeper, but also because it is much safer for me and for my buddy.
Yes, you can still screw up and die at 50 feet down, but at least the risk is a bit more manageable.