Apparatus for prereading film frames or the like

摘要

Apparatus for processing signals which are transmitted by the transducers of photoelectric cells scanning discrete marginal fields of square or rectangular film frames on a web of photographic film has relay-actuated switches which can connect the transducers of selected cells to each other and with the foreground and background inputs of a signal receiving circuit which is connected to the exposure controls of a copying machine or to a data carrier. The frames are examined by an attendant who energizes selected relays or several relays at a time to thereby cause the switches to transmit to the two inputs appropriate signals denoting the density and/or other characteristics of corresponding groups of neighboring marginal fields, depending upon whether the frame which is being inspected by attendant has been exposed in normal orientation, at right angles to normal orientation or upside down.