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Underwater Photography

There are no mysteries or problems in underwater work that cannot be overcome by almost anyone who wants to enjoy this least explored field of photography. 

Everyone with a still or cine camera knows that strange, inexplicable roving feeling - the desire to photograph something new, something exciting which has never been shown on the screen or seen on a negative before. Today there is little left on dry land for the photographer to satisfy the insatiable curiosity of his lens, and few people can set off for the poles, Everest or the jungles. Costeau had already been experimenting with underwater cameras and his famous film "THE SILENT WORLD" had won national acclaim. The Austrian Hans Hass, whose interest in diving dated back to the Goggle days was also cutting an important public figure. His film and books about underwater life were inspiring people all over the globe, who were now beginning to realize that it was more exciting to hunt with a camera than a spear.

Photography was also a booming hobby. Film was cheaper than ever before, equipment more versatile and easier to use. It was only natural that manufacturers, turned their attention to cheap underwater housings for use with automatic cameras that required little or no photography knowledge. What is more, you need not be a swimmer of Olympics standards to penetrate the mysteries of a river bed, or even the Mediterranean. And beneath the sea, something new and different can always be filmed, for in this strange world of silences there are valleys and grottoes where fantastic fish glide past in a liquid world of unbelievable colors; where sunken wrecks lie on the sea bed deep down, lost to the eye in a monochrome blueness. 

The most breathtaking film on sharks to be ever seen, costing 400,000 pounds to make and was an account of an expedition led by American Peter Gimble. The climax of the film was an encounter with the great white shark off the Great Barrier Reef. Filmed in 1969, by one of the world's most poetic underwater filmmaker, Stanton Waterman with Ron Taylor, "Blue Water White Death" has become a classic now.

The sea has beckoned the filmmaker again and again, resulting in such underwater classics like "Ereaserhead", "The Deep", "Jaws", "20000 Leagues under the Sea", "The Neptune Factor", "Abyss", to name a few. Besides, there have been films like "Below the 8FT Free", "800 Leagues down the Sea", "The Blue Lagoon", "Passion and Valor", "Return to the Blue Lagoon", "Castaway", where the sea was the backdrop against which the film was shot. Also, Costeau's "Secrets of the Sea" serial on underwater life was highly praised and led to growing interest amongst the people in this field.

Before going over the actual problems of picture taking, it might be well to review certain facts about equipments, particularly the design of underwater camera cases. Whether it is made of wood, fiberglass, brass, stainless steel, or Plexiglas, the camera enclosure should be as compact as possible. The more air inside a case, the more strength required to hold the air in and the more useless added weight to make the case sink. (Unfortunately, most of the Plexiglas underwater cases in the market today, particularly those of square cornered design, have so much excessive air space that they require two to five pounds of ballast before a swimmer can take them down. A properly designed case need not have a valve for pumping air pressure into the case before descending. There is too much chance of water pressure opening the valve mechanism (in many cases air pressures within the box tend to open a seal rather than let the increasing water pressure make the seal shut tighter).

Plexiglas seems to be the most popular material for underwater cases because it is easy to work with. It is strong, clearer than most glass, and welds into joints which are as sturdy as the material itself. Any cases built of this material, if at least three-eighths of an inch thick, should stand the pressure encountered at a 100ft depth if the air space around the camera is kept at a minimum. Plexiglas can be bought in tubes that can be heated and shaped into round-cornered rectangles when placed in forms, thus giving seamless corners.

Flat sided cases with cemented ends tend to squeeze inward to the danger point unless the Plexiglas is least three eighth of an inch thick. For smaller equipment, such as the exposure meter, the thickness can be reduced to one-fourth of an inch because areas and air content are smaller. Circular forms involve fewer pressure problems and can be more easily adapted to use.

Other materials that can be used are brass or stainless steel. Here good design and workmanship are of prime importance because leaks cannot be detected visually. There are three great advantages in metal cases:

  • easier control of the buoyancy problem. 

  • less possibility of scratching the lens-port surface.

  • no problem of internal reflection within the case.

There is no universal underwater camera enclosure that will work equally well with all 35 mm cameras. Such a case would have to be spacious enough to include the largest 35 mm camera, and therefore too large, in terms of air content for the smallest. The final solution is the Water-Tight camera. Such a camera is comparable in appearance, function and size to any camera and is completely waterproof throughout without the need of an enclosure. One such camera, the Calypso weighs no more than a NIKON SP, and has been tested successfully to 160ft. The Nikons All Weather 35 used without any housing. It has a 35 mm Nikon f/2.5 lens, shutter speeds to 1/500 sec, built-in flash synch, and features full use of controls while underwater.   

Operation of a Camera:

Let us assume you are on a boat anchored in 30ft of water in crystal clear conditions off the Bahamas. You are with a party of spear fisherman. Your camera is loaded with PLUS-X because such fast films have less contrast and more grain. There is plenty of light in such waters back of the sandy patches on the bottom which reflect back light. With camera and meter in case, you follow the others down, having been careful to keep your camera in the shade before the dive to prevent condensation due to temperature changes. You have also remembered to grease the "O" Ring which seals the back of the case. At 20ft you notice that your meter reads only about one stop more when pointed at your open palm than it did on your surface. You set your exposure accordingly and photograph your companion on the way down, having previously decided to use a shutter speed of 1/125 of a second since the action would be fairly slow. 

Upon reaching the bottom, you notice that there is good clarity and that the meter just above sand patches still reads within 3/2 stops of what is read on the surface. You click away until in a few minute you notice that objects aren't as clear as they were when you first descended. Your friend in search of fish and lobster have clouded up the water by stepping on the sand. Small particles have caused an underwater dust storm which has cut down the clarity of the water. The exposure meter reads the same as it previously read, but the contrast is gone.

Now you are in trouble, and there is nothing you can do about it unless you can change your film and expose with one or two stop less exposure, counting on forcing the developing to make up for the lack of contrast. This will gain back the lost contrast and add some grain, but the faint images you are now seeing might be saved on the film with such a change in exposure plus longer development. Still another way to compensate the problem is to use a wider-angle lens such as a 28mm or 25 mm. This will enable you to work closer to the subject.

More often the water is unclear not because of human disturbance but because of small organism suspended in the water over miles of area. Unfortunately, the wider the angle of the lens (beyond the angle of the good all-around standard of 35mm focal length), the less clarity in the corners of the picture. In a 25mm lens, almost a circle within the frame is sharp but falls off towards the corners. With the same kind of refraction one notices when looking into a fish tank at an angle. This refraction can only be corrected with expensive front corrections lenses mounted so that the outside element is in contact with the water. Such lenses, besides restoring sharpness to the corners of the picture, also bring back the same field of view that the lens had in the atmosphere. 

Still another phenomenon worthy of note is the focus shift attributable to the differences between the refractive properties of air and water. Focus should be approximately one-third to one-fourth closer than the actual distance between camera and subject. This applies only to cameras having a focus scale. When the camera is focused visually, as in a single lens reflex, the changes in focus setting become apparent on the ground glass.

Practically no cameras have a finder large enough to be used accurately underwater. The distance from eye to face-mask glass to rear eyepiece on camera is too great for accurate viewing, so it is important that large wire or elastic-on plastic finders be used for viewing. Too many commercially built underwater cameras cases merely depend on lining up dots, which isn't sufficient for proper composition of underwater pictures.

It is advantageous to have underwater cameras with negative-buoyancy. The cameras can be tied to a coral reef or sea fan and easily found when they are needed. In very deep water, where the bottom will not and cannot be reached, having cameras slightly buoyant is preferable because if anything goes wrong, one can let them go to be picked up later on the surface. When depth is unlimited slightly buoyant camera is preferable because it can be adjusted by weight belts. In shallow water when you might spend a long time on the bottom, it's better to be slightly heavy. This makes for steadier movie making.

Color Photography  

Color Photography is a real joy. In water that is slightly clouded by particles, color gives a better separation of values. In fact, color negative material can be used when black and white pictures are planned because better contrast is achieved with a color negative material.

In summer light it's surprising to find that within 10 ft below the surface of various bodies of water the exposure and color values need no corrective filters. When diving from 10ft on further down, surroundings become bluer and colors begin to change to the eye - red changing to brown and finally to black after 30 ft, while yellow and blue keep their values to greater depths. These changes are more pronounced on color films than they are to the eye. The CC-R series of warming filters will partially correct the cooling effect, as one approaches 40ft, but always at the expense of exposure increase.

Most top line 35 mm cameras are of the focal-plane type, which means that electronic flash will only sync around 1/60 of a second (except for 1/25 of a second in the case of a few cameras. Cameras with between-the-lens shutters have a definite advantage during conditions where there is a general daylight brightness and where flash fill may be too strong to balance properly. Cameras capable of exposure faster than 1/60 of a second will have a definite advantage in balancing existing light and flash.

Underwater Movies

Underwater photography doesn't take unusual physical ability, nor is it difficult to master technically. In fact, you can start taking pictures by snorkeling in shallow waters, or begin with the swimming pool. If the poetic motion of the depth, the changes of light and shade, and the shimmering ripple of the surface fascinate you, Still Photography will not be enough. There is little more effort required in making underwater movies, and the satisfaction is much greater. For underwater movies you must master an even kick with flippers and not twist your body from side to side - a sure sign of the amateur underwater movie maker. Cases for housing a small movie camera are as easy to build as still for still cameras.

Lots of divers look for a creative activity to further fulfill their underwater hours. Underwater photography is the challenge which many of them took up. How successful they have been was revealed in the brilliant display of underwater photographs exhibited at the first International Festival of Underwater Films, held in Brighton in 1965. Since 1965 the Brighton Film Festival which caters for both cine and still enthusiasts has become a stage where the world's very best photographers display mastery over the chosen medium - the underwater world of inner space.

It is no wonder that underwater photography is one of the most popular International hobbies. Growing by their thousands every year, millions take to the beds of oceans every year - even children are addicts, either with a spear, camera or just to look. But sooner or later they all want to record what they have seen on film.

13-Jul-2000

More by :  Subhajit Ghosh

Top | Computing

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