
Scuba Diving |
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The word scuba is an acronym for Self-Contained Underwater Breathing
Apparatus; a set of equipment that allows a person to breathe underwater
without having to rely on any form of assistance from above the surface.
Divers usually move underwater with swim fins (flippers) attached to their
feet and, depending on water temperatures, also wear a wetsuit. Subject to the reason for the dive, some divers also move around using a DPV (Diver Propelled Vehicle), commonly called a scooter, or may use a sled pulled by a boat. Some studies suggest the activity is high risk but this is often totally rejected by scuba diving enthusiasts. Although a degree of risk is involved, divers can reduce this with painstaking preparation, suitable equipment and attention to detail. One rule is paramount in the diving world: never dive alone, always dive with a partner – a so-called buddy, with whom communication is usually made by hand signals. The requisite diving skills are acquired though training courses and then honed by practice. The PADI (Professional Association of Diving Instructors) courses are the most widely recognized scuba certification courses in the world. Certification is based on individual performance, meaning that a certificate is first issued when an individual can demonstrate that he/she has mastered the necessary skills and possesses the required knowledge. The time needed to gain certification can vary widely. Beginner’s courses are usually split into five or six sessions. These can take place over an intensive three or four day period or can be spread over a few weeks. In terms of actual time, the norm is 25 to 30 hours of training. This includes theory and instruction in the pool followed by actual dives. Costs are difficult to assess as they vary widely throughout the world. Overall however, scuba diving is no more expensive than most other pastimes that require instruction and equipment. Once scuba diving skills have been mastered, many divers go on to take up underwater photography. This offers fantastic photographic possibilities in a totally different dimension to that on land. Nevertheless, underwater photography is far more than just swimming around with a waterproof camera or a camera in a special waterproof housing. As colour is absorbed as it travels through water, one of the main problems is the loss of colour and contrast at any significant depth or distance. This also applies in what may seem to be crystal-clear water. The way to overcome this problem is to use a wide-angle lens and get as close to the subject as possible; ideally no more than one metre away. This of course requires patience and calm, unhurried movement on the part of the diver. The alternative for restoring colour is to use flash. With the advent of through-the-lens metering and instant viewing on digital cameras, underwater flash photography has become much easier to use, if not to master. The digital darkroom also comes into its own in underwater photography. |
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