Electronic light metering for automatic exposure cameras - using sensors with different spectral sensitivity and evaluating digitised signals according to film spectral sensitivities

摘要

An electronic illumination measurement method involves simultaneous detection of several different spectral regions, esp. the range from the short to the long wave regions of white light. Several sensors are used with different spectral sensitivity curves. The sensor's analogue signals are converted into digital signals characteristic of the illumination intensities in the different spectral regions. The digital signals are electronically evaluated according to the relative spectral sensitivities of selected photographic recording materials and signals are generated corresp. to the required illumination duration and/or aperture values. USE/ADVANTAGE - Automatic exposure control for cameras. Ensures minimal measurement inaccuracy, takes account of the latest emulsion technology and ensures matching to selected photographic materials.