Parallax compensation

The parallax is at Sucherkameras necessary to a better match of the viewfinder shown image section with the fact from the lens to the film to achieve the projected image.

The so-called parallax arises from the fact that with the viewfinder camera, but also with two-lens reflex cameras, the image displayed in the viewfinder is not reflected from the beam path of the imaging lens ( single-lens reflex camera ), but from its own optics, which are arranged offset parallel to the taking lens, is projected. The resulting effect is primarily a "shifted" image section. The viewfinder image also shows a different perspective (this effect is, however, very small under normal shooting conditions and of little importance in photography). The smaller the distance between the camera and the object, the greater the parallax effect.

The parallax compensation tries to reduce this effect, for example, by rotating the viewfinder or moving the image limit marks in the viewfinder. Typical examples of cameras with parallax compensation are the Leica-M cameras. The parallax compensation depends on the focal length used and the distance set. With two-lens reflex cameras, there is typically no parallax compensation. However, when using close-up lenses, compensation can be achieved by using a prism in front of the viewfinder lens.

The parallax compensation can only minimize the difference between the viewfinder image and the photo. A complete compensation is geometrically impossible (or only achievable for the image boundaries if the perspective continues to be distorted). Even the exact correction of the image section is very complex. In the case of simple cameras with a line-of- sight viewfinder , therefore, usually only an additional marking is made for the image section at the shortest possible distance setting.

Higher-quality riflescopes have devices for adjusting the parallax compensation.