Abstract: Automatic control apparatus for a photographic camera is responsive to a set of measured scene parameter inputs, representing at least subject distance and subject brightness, to produce signals representing the desired setting of one or more of the following camera control functions: aperture size, shutter time, flash output, and lens extension. The desired camera settings are determined by a mapping function defining the settings that optimize picture quality by minimizing the total reduction in picture quality due to the combined effects of blur, smear and exposure error. The mapping function is obtained by maximizing a Composite Quality Factor comprising one or more Subjective Quality Factors representing blur, smear, and exposure, evaluated at the subject distance and at a plurality of background distances.

Abstract: A photographic camera recognizes when a partially used film cassette is reloaded into the camera. Following the loading of such a cassette the camera drives the film to position an unexposed film frame for exposure.

Abstract: A focusing device for use with photographic cameras and the like. This invention uses a light source such as an electronic flash to direct light toward an object to be photographed. When the amount of flash light reflected by the subject reaches a predetermined level, a quench circuit is activated which terminates the light emanating from the light source. A timer measures the elapsed time between the depression of the body release and the generation of the quench signal. Converter means translate the measured time interval into a range signal that is functionally related to the distance between the focusing device and the subject. The range signal may then be used to adjust a camera component such as a lens or may be used to control visual indicia that present readings to the operator indicative of range.

Abstract: A quenchable electronic flash for use with a camera having an M-contact flash synchronization device, includes a flashtube for producing light, a light-responsive integrating circuit for producing a flash terminating signal when the quantity of light measured by the integrating circuit reaches a predetermined level representative of a desired film exposure, and a quench circuit responsive to the flash terminating signal for terminating the production of further light by the flashtube. A time control circuit, responsive to actuation of the flash synchronization device, energizes the integrating circuit substantially with initial opening movement of a shutter of the camera. As a result, the integrating circuit is prevented from responding to any light prior to initiation of an exposure interval and responds to a quantity of light that corresponds substantially to the light, e.g. ambient as well as flash, impinging on film in the camera during an exposure.