As a working professional, I get asked frequently by divers I meet what kind of gear do I use and why.
I will start with dive equipment. For at least 10 years I have used Sea Quest BCD's and been quite happy with the quality, construction, and durability. Five years ago or so I got an Atomic Titanium regulator. It was expensive and worth every penny. It is by far the best breathing regulator I have used. I have an oceanic wetsuit and set of split fins that are 4 years old, and while the fins still work great the wet suit is ready to be replaced. I also use a pair of Cressi free diving fins when doing blue water snorkeling with whales. I love the power.
For topside images, I use the Nikon D3 , D2X, D700 bodies. For
underwater photography, I use the Nikon D300. As I do a lot of scuba diving & blue water snorkeling I found that I need a housing specific to each purpose. The Ikelite features ttl flash exposure compensation which is very cool and allows me to concentrate on composition. I can adjust the ttl exposure by 1/3 f-stops by rotating a dial, rather than reaching out and changing strobe settings. The only negative with the housing is the way ports attach. The system relies on pressure to seat the o -ring. When using the housing while scuba diving the pressure seats the port and there are no issues. I cant say the same when snorkeling with the Ikelite housing.
That why I also use the Nexus housing. Simply put its small and built like a tank. The quality of the 10-17 optical glass port cant be beat. The negative of this system is that to take advantage pf the glass optics, you need a port specific to each lens and that is expensive. The 10-17 port cost just under a thousand bucks. The system has 2 sync ports for traditional strobes and 2 fibre optic ports for high tech digital strobes.
I use the following lenses. The 10-17 fisheye zoom Tokina, 10.5 mm fisheye, 16 mm fish eye, 60 & 105 macro Nikon lenses. For strobes I use three Ikelite DS160's. The strobes have ttl and manual power settings. They are 5000 degree kelvin in temperature which produces lovely blues and requires less time spent in photoshop. I also use two Sea and Sea YS 300 strobes from the film days that only work on manual settings. I love using them as slaves, set 1-2 stops lower than the main light to create rations and dimension in my images. Too many times a ttl exposure will result in flat lighting. This is when there is an equal amount of light throughout the scene. When creating light ratios underwater the light is not even so there is more shadow detail and depth to the image.
When I travel, I use Tamrac back backs, Velocity 9x camera bag, and Rolling Studio case featuring plastic armor. These products are light weight yet heavy duty. The amount of equipment they accommodate is impressive as is the style and appearance. I bring a Mac lap top, 3 external hard drives for back up, 3 - 16 gig cards, 8- 8 gig cards, 3 - 4 gig cards.I bring an I-phone loaded with 2 movies and Skype .
Other bits include a small glass reflector for the BCD pocket, as well as a safety sausage and a whistle. These are items I hope not to use, but am glad to have with me. I use the Aladin Nitrox computer, but tend to keep it set on air for added safety.
The last thing I pack is a sense of humor and a bit of patience. The wonderful thing about traveling is that there is a lot of time spent waiting. Rather than get frustrated, I just go with the flow.