Like Macro work where basic optical principles become and issue underwater photography has its own issues. Underwater light changes and becomes more blue - the deeper we go the more it changes. The intensity of light also drops off the deeper we go down and the clarity of the water also plays a part in what the image looks like.

Nikonos II - The standard lens for this camera is 35mm - on land it gives a wide angle view- under water it give a standard angle of view.

.This is why many underwater photographers use flash lights or strobes. I find it interesting that the first flash bulb was actually designed by Louis Boutan in 1893 in an effort to make pictures underwater. To allow the magnesium to burn underwater, the substance was encased in a watertight bulb filled with oxygen. The bulb was ignited by heating a fine platinum wire with electrical current.

Fine particles suspended in the water no only obscure vision, they reflect light from a flash or other light source.

 

Hanimex Amphibian

 

This is the Minolta Weathermatic A, a waterproof compact camera which uses 110 size cartridge film, made in Japan and dating from the 1980s.  The camera can be used underwater at depths down to 5 metres, the specification is as follows:   Lens: Rokkor 1:3.5/26mm (4 coated glass elements in 3 groups)
Focusing: five distances selectable by turning the knob with the 5 distance symbols
Shutter: metal blade shutter with fixed speed 1/200 sec.
Aperture: 3 apertures selectable with a knob, one for sun, one for clouds or one for flashlight
Viewfinder: bright frame finder with parallax correction marks, low light indicator and focusing symbols
Flash: bult-in, selectable with aperture switch
Film advance: by lever

 

The focal length of the lens also changes underwater. So a 35mm lens on a 35mm camera is actually about 50mm. We can see this effectively when we take images with the lens half out of the water and half under where a leg or are of a person is distorted.

 

 

Nikon Compact 35mm film camera - This compact camera has many features - auto focus - auto exposure- built in flash and limited manual features

 

Surfing
While the wide-angle lens gives a wonderful perspective and a great depth of field that he has used in many of the water shots, it also means that the photographer has to be very close to the action to fill the frame. In any of the images where the lens is partly underwater, you might notice that the perspective changes.

Under water the focal length of the lens is increased by about a third. This means a 35mm lens on a 35mm camera actually gives the same perspective as a 50mm lens in air. Water drops of the surface of the lens can also be a problem and many photographers use a wetting agent that releases the water evenly.

If you really want a blast track down the classic movie by George Greenough titled Crystal Voyager – the last 13 mins have the most amazing footage – Pink Floyd wrote the sound track for free. Greenough was the first master of this. Also check out a series of movies titled the history of surf cinema photography. It will give you a context to the history of film.

 

Kodak disposable

Kodak water and sport camera