Digital Underwater Photography

These are compact cameras with no A (aperture priority), S (shutter speed priority) or M (manual shutter and aperture) manual controls. At most they feature a mode with underwater-specific settings.

The main technical characteristics for underwater usage are:

Availability of underwater housing: indispensable, of course.

Max operating depth: depends not only on housing resistance, but also on operability of buttons at high pressure.

Strobe diffuser: fixed or mobile, recommended for better performance.

External strobe availability: depends on the presence of a hot-shoe connector on the camera and on the case (either by cable or hot-shoe), or on the possibility of controlling an external strobe using an optical fiber cable connected to the on-camera strobe.

Availability of additional lenses: some housings can mount macro and/or wide-angle lenses for improved versatility.

Wide-angle zoom: rather than the focal range of the lens (usage in tele postion is very limited), what really makes a difference is the minimal focal length (expressed in mm as 24x36 focal equivalent), providing as wide as possible a view angle.

Macro: the minimum focusing distance in macro mode, expressed in cm, gives a measure of the quality of small abject images; ina addition, the minimum focusing distance in tele mode is also important because the strobe light diffusion is more uniform at not-too-close distances.

Stabilizer: very useful because cameras tend to select long exposure times underwater with ISO not too high (high ISO's are not recommended for good image quality).

Underwater specific modes: for cameras with no manual shutter speed and aperture control, dedicated modes optimize the relationship between available light and strobe light and often introduce chromatic corrections that can worsen image quality.

Display dimensions: in inches: the larger the viewer the easier is subject framing. Visibility in strong light conditions is also important.

Megapixel: a higher number of pixels is not necessarily a synonym of better quality, which instead is mainly related to individual pixel dimensions.

HD video: ensures better video quality.

Price: in US dollars "from"; should be judged considering both camera features and comparison with equivalent non-amphibian cameras with separate casing.