Digital Single Lens Reflex (Digital SLR or DSLR) cameras use a mechanical system to allow the image coming through the lens to also be viewed through the camera's viewfinder. This class of camera is the primary digital type used by professionals and are usually compatible with the lenses used on older Film SLR cameras.

Digital Single Lens Reflex (Digital SLR or DSLR) cameras use mirrors to allow the image coming through the lens to also be viewed through the camera's viewfinder. The mirror is flipped out of the way when the photographs are taken.

This class of camera is the primary digital type used by professionals and are usually compatible with the lenses used on older Film SLR cameras. Practically all DSLRs have the ability to change lenses, giving the photographer a much wider selection of specialized lenses.