Nikonos IV-A with 35mm f2.5 with manual
Our friend Ken Rockwell writes: This is the classic Nikon underwater camera. It's built like a tank and needs no additional housing for depths to 160 feet (50m). It has interchangeable lenses. The most popular lens is the 35mm f/2.5 which may be used on land, sea or air; in fact, this is a great camera for use in dirty, dusty and wet environments.