Sample Notes from the text 'Underwater Cameras' Original: Underwater Cameras Regular cameras obviously will not function underwater unless specially protected. Though housings are available for waterproofing 35 mm and roll-film cameras, a few special models are amphibious –they can be used above or below the water. Most of these cameras are snapshot models, but one, Nikonos, is a true 35 mm system camera. Though lenses and film must be changed on the surface, the camera will otherwise function normally at depths down to 70 mm. Four lenses are available : two of these , which have focal lengths of 90 mm and 35 mm, will function in air and water; the other two of these, which have focal lengths of 90 mm and 35 mm, will function in air and water; the other two, the 28 and 15 mm lenses , work only under water. Lenses are also available from other manufacturers. Sample Notes: Underwater Cameras 1. Regular Cameras special housing necessary 2. Amphibious a) snapshot models b) Nikonos (35 mm) Lenses i) air & water 35 mm ‘ 90 mm ii) only under water 28 mm 15 mm

Source: Freeman M. The encyclopaedia of practical photography London, Quarto Books 1994, p283