Underwater photography a favorite pastime for Beverly dive shop owner

BEVERLY ? Becoming an underwater photographer opens up opportunities that relatively few get to experience and the North Shore is an ideal place to get started.Bob Boyle of Rockport, owner of the Undersea Divers dive shop on Water Street, knows the rewards of such a pastime. So does Andrew Martinez of Wenham, a professional underwater photographer whose work has appeared in National Geographic World magazine. Both aquatic adventurers are readily aware that using a camera proficiently underwater isn’t something a novice diver should expect to do, mostly because the art requires first learning how to balance your body in a liquid matrix with a heavy metal tank on your back.Sure, you can go below in a submarine and shoot through the portals, or skip the scuba tanks entirely and simply go snorkeling, but such choices come with significant limitations.According to Boyle, whose many students include divers from the North Shore, Greater Boston and New Hampshire, most advanced underwater photographers agree that buoyancy skills must be near perfect if the shooter expects pleasing images. Strong currents often toss divers into fragile reefs, damaging or destroying precious coral as they flail around with their fins and other equipment. This kind of misadventure can lead to bad reputations. That’s why aspiring underwater photographers should first become certified divers through an organization such as Professional Association of Diving Instructors (PADI) and then enroll in a specialty course tailored to taking pictures beneath the surface.Boyle’s dive shop is perhaps the most popular and busiest in the region. Each year, its instructors certify hundreds of new divers who then ply the rocky waters off Rockport, Gloucester, Nahant and other locations known for interesting marine life. Once certified, Martinez teaches many of them how to handle a camera under the surface.A former Spanish teacher at Masconomet Regional High School, Martinez has taught underwater photography classes at the Beverly dive shop for nearly 20 years, and regularly gives workshops in Marine Life Identification and Underwater Photo Theory and Practice to area research groups.”My advice would be to get certified first and hone your diving skills. People like to rush into it, but you can’t. It isn’t so much the physical part of it. Your buoyancy is so important. If you’re banging up the bottom with your fins, you’re going to be kicking up sediment. That’s the No. 1 problem that will destroy your photo possibilities,” said Martinez, whose photo assignments for National Geographic World magazine have taken him to Fiji, Bonaire and Cape Cod.Beyond that, getting comfortable in the water is paramount.”You can’t be worrying about and constantly checking your equipment or adjusting your straps. You need to be comfortable, and when that becomes second nature, you can concentrate on your photography,” Martinez said.Boyle has annually led diving groups to Bonaire and other Caribbean destinations. Martinez has guided marine biology students and travel groups to the islands of Galapagos, Cayman, and the Bay Islands of Honduras, places where he has captured some of his finest images. In recent years, he switched from film to digital, and is in the process of scanning thousands of color slides.Although Martinez shoots with a Nikon D300 digital SLR camera and an array of lenses with macro settings for close-ups, he suggests beginners purchase a digital point-and-shoot capable of being submerged to 30 feet. The latter models cost less than $200.”One of the most important things about underwater photography is learning to be patient. You have to wait. Then get close to your subject, which means your diving skills must be OK. Then you’re on first base,” he said.Professionals suggest novice divers work on their hand movements by tying knots in a length of rope or writing on a plastic slate while under water. Taking photographs of objects at the bottom of a swimming pool is also recomme