An underwater digital camera is a digital camera which is designed to function underwater. It may take still or video photography or both, depending on the model. Such cameras tend to be more expensive than comparable models intended for dry land because they have to be carefully constructed in order to protect the integrity of the camera. These specialty items can be found at some camera stores, ordered through manufacturers, and purchased or rented through companies which supply equipment to people who work in and around the water.
Several features can be seen in an underwater digital camera. The first is a housing which will keep the camera safe in the water. This tends to make the camera more bulky. The camera may also have specialty lenses which are designed to work more effectively in water, including lenses which resist fogging and beading of water. The controls available to the operator may vary, depending on the models. The camera may also have oversized handles so that people can more easily grip it while they are underwater.
Like other digital cameras, underwater digital cameras store images digitally. This may be done on memory cards, portable hard drives, or flash drives. The stored images can be transferred to a computer for review and editing. Some cameras may provide integrated editing and the camera may have a view screen in addition to a viewfinder which provides information about what the camera is seeing. Depending on which lenses are used, the depth of field can vary, and an underwater digital camera may have a lens mount which allows users to swap lenses for different settings.
An underwater digital camera can also have some unique features for challenging environments. It is possible to take pictures in very deep water in the ocean with specialized cameras which have been designed to resist extreme cold and pressure. Such cameras may be sealed with oiled gaskets which help the camera maintain its shape, and they can be outfitted with insulated cases so that they will not fail in the cold.
An underwater digital camera may be handheld by an operator, mounted in a boom, or attached to a seagoing robot or sledge. In harsh environments, for example, divers cannot safely be in the water to handle cameras and thus remotely operated cameras must be used. By contrast, operators with handhelds are more commonly seen in environments where a robot or sledge might be difficult to operate, such as coral reefs where there are concerns about impact damage.