In a dive site called Tiger Beach in the Bahamas. It is named after the Tiger Sharks present in this location, even though it is a Lemon Shark in the photo. Tiger Beach is quite far from the land but it is named a "Beach" because of its shallow water (15-18 feet) and white sandy bottom
Time
It was taken sometime between 3pm and 5pm
Lighting
Two Sea & Sea strobes that helped lighting the belly of the shark. The ambient light was controlled by the shutter speed.
Equipment
Canon G10 camera with a wide angle port and Two Sea & Sea strobes
Inspiration
Sharks have reputation of evil creatures and it is so untrue. They are predators, this is true, but humans aren't their main course..
Editing
A little sharpening and noise reduction, some white-balance correction but the RAW image came out already quite good
In my camera bag
For underwater photography I use a compact, fully manual Canon G10 with 2 Sea & Sea strobes, a wide angle port, a close-up diopter, a high intensity focus light for macro shots, a night-vision kit for shooting florescence creatures, many rechargeable batteries and chargers, a laptop.
For land photography I take my Pentax K7 and K5 bodies with a variety of lenses, depending on the type of trip and photography. I also take graduated filter for landscape photography and a flash. A compact carbon fiber tripod is also with me on every trip.
Feedback
Before taking cameras on such scuba diving trip make sure that you have enough experience as a diver. If you want to focus on the camera then everything else must come to you naturally such as buoyancy control.
Most sharks are shy. If you look straight at them they will probably swim away. Stay low, look away and as the come closer turn and take the shot.
Don't zoom in with your lens. Zoom with your fins! The water density is much higher than air so you want very little water between you and your subject. In simple words - Get closer!!
Be safe and always care about you and your dive buddy before your equipment or your shots!!