Underwater Videography - Limitations

Limitations

The primary difficulty in underwater camera usage is, of course, sealing the camera from water at high pressure, while maintaining the ability to operate it< The diving mask also inhibits the ability to view the camera image and to see the monitoring screen clearly through the camera housing. Previously the size of the video camera was also a limiting factor, necessitating large housings to enclose the separate camera and record deck. This results in a larger volume which creates extra buoyancy requiring a corresponding use of heavy weight to keep the housing underwater (about 64 lbs. per cubic foot of displacement or 1 kilogram per litre in the ocean). Early video cameras also needed large batteries because of the high power consumption of the system.

A final problem is the lower level of light underwater. Early cameras had problems with low light levels, were grainy, and did not see much color underwater without auxiliary lighting. Large unwieldy lighting systems were problematic to early underwater videography. And last, underwater objects viewed from an airspace, such as the eye inside a mask or the camera inside a housing, appear to be about 25% larger than they are. The photographer needs to move farther back to get the subject into the field of view. Unfortunately that puts more water between the lens and the subject resulting in less clarity and reduced color and light.