Found in a camera with the ability to keep its mirror in the up position to prevent vibration from mirror movement in a long exposure. Locking up the mirror may also permit certain specialty lenses to be attached that would otherwise come into contact with the mirror, and in some digital cameras, keeps the mirror out of the way when cleaning the image sensor.Photo Tips
Lens with an internal mirror or mirrors that are usually curved, enabling comparatively-light lenses that are shorter than similarly-designated long focus lenses.
A lens where the light path is bent and reflected internally to increase the focal length of the lens a simplified system that is usually less expensive than conventional super-telephoto (300mm and up) lenses.
An ancient and honorable way to stretch your lighting resources and the sun s reach. For table-top shots keep a few shaving mirrors handy for accents and Kicks. A little tape applied to the mirror can shape the reflected light beam; dulling-type spray can diffuse it.
Internal area of DSLR housing mirror, open area behind lens mount, in front of sensor. Viewable when lens is removed.