PHOTOGRAPHIC CAMERA AND EXPOSURE CONTROL SYSTEM

摘要

A microcomputer is used in an exposure control system and method for developing and controlling execution of a film exposure strategy based on selected pre-exposure inputs including scene brightness level and camera-to-scene distance. The computer is preprogrammed with shutter trajectory and strobe operating parameter data bases. In the ambient light mode, a trajectory signal program correlated to the scene brightness level is developed and fed to a stepper motor which drives a dynamic aperture shutter in a manner whereby its operation is characterized by an aperture size versus time trajectory curve defined by the developed signal program. In the strobe flash mode, the trajectory curve correlated to scene brightness is tailored to enhance flash mode operation and an appropriate strobe firing aperture and quench time is automatically selected in accordance with both the brightness and camera-to-scene distance inputs to control the strobe contribution to exposure value.