Means and method for calibrating light responsive exposure control system

摘要

A light attenuating filter is provided for a light responsive exposure control system in order to facilitate calibration of the exposure control system so that the amount of scene light admitted by the exposure control system during an exposure interval will substantially correspond to a particular film speed. The exposure control system is of the type having a light detector wherein the light attenuating filter is movable into intercepting relation with a select portion of the scene light directed toward the light detecting means. The select intercepted portion of the scene light is determined and fixed during the manufacture of the exposure control system in order to provide the requisite output response from the light detecting means to terminate an exposure interval in time to insure that the amount of scene light admitted during the photographic cycle substantially corresponds to the select film speed.