Exposure ascertaining device for cameras

摘要

An exposure ascertaining device for cameras, in which the exposure of the film is ascertained on the basis of variations in an output from a photoelectric element disposed in a position where said photoelectric element can receive the incident light passed through a film. An exposure ascertaining device for cameras, comprising a photoelectric element disposed in a position which is away an optical path in which such a part of the incident light that enters the surface of a film and which position permits said photoelectric element to receive such a part of the incident light that advances toward a film-surrounding region of a film-set side of the camera. Another photoelectric element disposed in a position which permits the same photoelectric element to receive the light reflected from the film-surrounding region of the film-set side of the camera. The movements of movable members which are adapted to be moved when the film is exposed are ascertained on the basis of outputs from said photoelectric elements.