Chris Crumley is one of the most recognized underwater photographers in the world. Over the years, his advertising and editorial work has appeared in hundreds of pages of SCUBA-related marketing materials, travel brochures and a wide range of publications.

Most photographers are known for a particular specialty, Crumley is known for working with people underwater, and he’s turned it into a special “art.” His ability to capture unique moods and colorful backgrounds combine beautifully with skilled models to produce consistently stunning and memorable underwater images.

Crumley and one of his models, Sherry Smith, developed a unique training program for underwater models. Here Crumley shares some of their secrets on “What Makes A Great Underwater Model”

Desire: A model has to WANT to be there and it shows in the shots. Even underwater, you can’t hide certain things. A desire to make pictures that speak, excite and provoke emotion are intangibles necessary with every underwater model. This trait works in tandem with a desire to share the underwater experience with others.

Attitude: A model needs to be enthusiastic, creative, willing to deal with the elements, be patient and be part of a team to be successful, Crumley explains. “It’s not as simple as getting in the water and looking at the camera. There’s a lot that goes into every shot and a good model must have the right attitude.”

Body Language (Attitude): It’s more than just being a good diver. Top underwater models know how to move through the water effortless. They use their fins to propel and steer themselves – not their hands (a common mistake). In fact, a good model’s hands fall naturally alongside the body. The EYES are a major part of quality underwater shots. The diver’s eyes don’t look straight at the camera but at the subject. “I like my models to ‘smile’ with their eyes,” Crumley says. “Expressive eyes – no stares – give every shot an added boost.”

Communications: You can’t talk underwater, but it’s necessary to communicate. This comes from preparation in advance of a shoot. Experienced divers have their own sets of hand signals. It’s no different for underwater models. “Sometimes you don’t have to do anything other than point, other shots require a bit more communication between photographer and model.”

Buoyancy Control: If you’re not a diver, you won’t understand. If you are a diver, you have to appreciate the incredible buoyancy control every good underwater model has mastered. They know how to “hover” over a reef using partial breaths to rise and fall small amounts; they move effortlessly and stop on a dime – despite all the gear, currents and unique surroundings. “We practice this skill a lot because it doesn’t come naturally,” Crumley points out. “But once you master buoyancy control as an underwater model, you are a step ahead of most SCUBA divers.!”

For the past 14 years, photographer and filmmaker Jill Heinerth has been exploring underwater caves around the world, from lava tubes off the coast of North Africa to icebergs in the Antarctic. Wired.com recently caught up with Heinerth to talk about some of her most exciting cave diving moments, as well as the recent technological advances that have made cave diving easier, safer and more accessible to recreational divers. This gallery showcases some of Heinerth’s best underwater images and includes captions adapted from our conversation with her.

Above: “My Neighborhood Cave” in High Springs, Florida

Heinerth snapped this photo of herself as she descended through the tannic water of the Santa Fe River into her neighborhood cave in High Springs, Florida. The swirling orange blaze above her comes from the mixing of river water, stained red by decaying cypress trees, with crystal blue spring water flowing from the cave. The giant black mask she’s wearing is connected to a special diving tank called a rebreather.

“Basically, it does the same thing as a space suit,” Heinerth said. “In normal scuba gear, you’re inhaling gas and exhaling a column of bubbles into the water. But in a rebreather, you’re actually recycling your air, with carbon dioxide getting scrubbed out of the mixture and oxygen getting added back in. With an electronic rebreather, you can tune the gases that you’re using, so that in deeper water you can use helium and other gases to get the optimal mixture of breathing gas for deep water.”

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