Dark slide (photography)

In photography, a dark slide is a wooden or metal plate that covers the sensitized emulsion side of a photographic plate. In use, a pair of plates joined back to back were used with both plates covered with a dark slide. When used, the dark slide is removed for the period of the exposure and then replaced.

A dark slide is used for magazine backs on medium format cameras such as Hasselblad and Mamiya, and plate holders on view cameras, like the earlier Reisekamera.