Angle finder
An angle finder is an accessory part of professional photo cameras. It is attached to the viewfinder of the camera or screwed into a thread provided for this purpose and deflects its image via a mirror or a prism (usually 90 degrees) so that the viewfinder image can be viewed from the side or from above. So the photographer can have a more comfortable viewfinder. This is especially true for recordings that are made from a very low camera position or in other situations in which the eye cannot be positioned behind the viewfinder. The angle viewfinder is usually rotatable and provided with a diopter correction , so that a 90-degree view is possible from any direction and without glasses. There are also angle finders which offer the possibility of an adjustable magnification - mostly of a low factor (e.g. 1.0–2.0).