Diving with sharks is like hiking in grizzly bear country or watching lions on safari. People are fascinated with sharks, and there's a visceral reaction to finding yourself in the domain of an apex predator (like the shark on the right that I photographed in Fiji). If you can get the theme song from Peter Benchley's movie  out of your head, it can be an amazing and thrilling experience to swim with sharks. Capturing images of these spectacular animals in their natural habitat can be even more rewarding.
Attempting to photograph large, fast-moving predators is not like shooting reef fish, corals, and nudibranchs. Most sharks don't stay still for very long, and can move quickly and erratically.
Settings: ISO 200, 1/125 @ f14
This shark was shot at a depth of about 60 feet. I used a 15mm fisheye lens and waited to fire the shutter until the very last moment, when the shark in the foreground was no more than 18 inches from my camera's dome. The strobes were set near full power to illuminate the shark's profile, as well as the sponges and snappers in the background.
Settings: ISO 200, 1/10 @ f22
For this image, I decided to experiment with slow shutter speeds to create a blurred effect from the movement of the shark. I was at a depth of about 50 feet and used a 17-35mm lens; again, I waited until the very last second to fire the shutter when the shark was very close to me. With the strobes on full power, I shot dozens of frames in this manner, making constant adjustments to shutter speed and aperture, until I captured one I liked.
Settings: ISO 200, 1/125 @ f11
Late in the afternoon, with the sun very low in the sky, I decided to switch from a wide-angle lens to a 60mm macro lens. This was a little unconventional because you generally don't shoot large animals with a lens made for shooting small ones. But with low light levels and somewhat murky water, the conditions weren't favorable for nice, blue, wide-angle shots. I used a fast shutter speed here since macro lenses are much less forgiving than wide-angle lenses in freezing the action. I snapped this image just as the Lemon Shark was turning in front of me with a toothy "grin" on its face.
When preparing to shoot in an area known for sharks, do your homework, learn as much as possible about what you will encounter on your trip, and visualize ahead of time the shots you want to capture. Experiment with your settings! This can lead to some creative and dynamic images; don't be afraid to try something new.
As with all dives, remember to tear your eyes away from the camera now and then to simply watch the majesty of these incredible creatures. It's a thrill and a privilege to witness sharks underwater. But the speed with which they are disappearing from the ocean means we might not see sharks for much longer. Groups like CORAL are doing what they can to prevent this potential tragedy and need our support to help save these wonderful animals.
Have fun and dive safe,
To view more of Jeff's work, log on to: www.jeffyonover.com 
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