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Cameras - Amphibious or not?
Reproduced from in focus 15 (April 1986) There is no commercially available amphibious camera which has reflex viewing and a wide choice of lenses. And, doubtless, If there was it would be prohibitively expensive. For this reason underwater photographers have to make a choice between an amphibious camera and housing a land camera. HOUSINGS - THE ADVANTAGES The biggest single advantage of using a land camera in an underwater housing is that you can have reflex (through the lens) viewing. This allows you to see exactly what you are photographing and to cheek whether your subject is in focus and that the shot is correctly composed. The
best camera for housing is one whose standard prism can be removed
and replaced with a larger prism designed to allow the whole image
to be viewed from further back. Prisms that can do this are called
Actionfinders or Sportsfinders and are available on the top of the
range cameras from Nikon, Canon and Pentax. There is a wide range of land cameras available, so you have quite a choice, and the range of lenses is almost limitless, from circular fisheyes to long telephotos, The only limitation being whether the housing can accommodate the lenses of your choice. However, because you are using a land lens underwater, some distortion to the Image may occur and the angle of coverage behind a flat part will be reduced. Fortunately this is easily overcome, as most housings have correction ports available to restore both the optical quality of the lens and its angle of coverage. Perhaps the most useful lenses are the "macro" lenses, which can focus from infinity down to a few inches. These are very versatile, especially for marine biology/natural history shots. Like most people, you probably already own a land camera. You should, however, consider very carefully whether it is suitable for use in a housing underwater. Unless it has reflex viewing, interchangeable lenses, and control over aperture and focusing then It probably isn't. Finally, there must be a housing available or you must be prepared to build one, either from a kit or from scratch. An additional feature of using a land camera in a housing is that you can choose which film format you want to use. Housings are available for all formats from 110 to 6x7cm HOUSINGS - THE DISADVANTAGES Land cameras in housings are, by comparison with amphibious cameras, bulkier and heavier. To what extent depends on the individual manufacturer, There are modern housings available which are as small as they possibly can be, since they are designed with one particular camera in mind. These tend to be more expensive than the larger housings, which can be adapted to fit a wide range of cameras. For those of you who travel overseas, the bulk and weight can cause problems with transportation and the odd shape housings demand a very large case. It is often better to dismantle the housing for the journey and reassemble it on arrival at your destination, The cost of housings is high. This is because manufacturers cannot make and sell them in such large numbers. A commercially available polycarbonate SLR camera housing is almost the same price as a Nikonos V with a 35 mm lens. Move to an aluminium housing and you soon overtake on price. Installing your land camera in a housing involves attaching linkages onto the aperture, shutter speed, focus, shutter release and wind-on controls. These are fine once set, but can be fiddly and prone to misalignment when you are underwater. It is often simpler to commit a camera to use in a housing, so that the setting up procedure need not be repeated each time you want to take photographs underwater. AMPHIBIOUS CAMERAS - THE ADVANTAGES All amphibious cameras tend to be smaller and lighter than housed land cameras. Their outer shell is the housing and the controls are purpose designed and permanently attached, so there is no setting up procedure each time you want to use the camera. Despite being non-reflex, amphibious cameras are quite versatile in most areas. The Nikonos range are excellent for close-ups and macro shots, where a frame is used to delimit the subject area and focal distance and when used with wide-angle lenses are a small and easily operated package. These two areas represent the majority of underwater shots. Despite the limited choice of amphibious cameras, there is a wide range of accessories available which make them very versatile. This is more true for the Nikonos than other cameras, With the appropriate accessory the Nikonos is capable of taking almost any underwater photograph required. Finally, if you wish to, it is much easier to sell an amphibious camera than a land camera in a housing, AMPHIBIOUS CAMERAS - THE DISADVANTAGES Being non-reflex is the amphibious cameras downfall. Not only is it more (not to mention difficult to compose your shots but it is not possible to continually focus on your subject. However, with the available accessories, and bearing in mind the limited range within which most underwater photographs are taken i.e. close-ups or wide-angle, then amphibious cameras do fit the bill in a surprisingly simple and effective package, There are far fewer amphibious cameras to choose from and, bearing versatility and serious use in mind, there is really only the Nikonos. This is a specialist camera which not all camera repairers can repair, should something go wrong. In out of the way places you may have difficulty having the camera repaired. CONCLUSIONS There is no SLR amphibious camera at a reasonable price with good interchangeable lenses, so we have to make the most of the equipment available and settle an a compromise. No
conclusion in favour of one particular system can be reached, as
the needs and tastes of the individual vary and indeed |
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