GB1456346A - Camera exposure indication device - Google Patents

Abstract

1456346 Cameras PENTACON DRESDEN KAMERA-UND KINOWERKE VEB 21 Feb 1975 [22 Feb 1974] 7426/75 Heading G2A A camera has a first control circuit (not shown) arranged to produce an output dependant on scene brightness and exposure factors set, at least one indicator light 1, 2 controlled by the first circuit (in Fig. 1 via resistors 5, 6) and a second control circuit 7 to 16 having a photo-sensitive element 16 exposed to scene illumination or to the image of a scene in the camera view-finder, the second circuit being coupled to the or each light 1, 2 so that the brightness of the latter depends on the brightness of the scene or view-finder image and thus remains clearly visible. In Fig. 1 lamps or L.E.D.s 1, 2 are connected via transistors 3, 4 and resistors 5, 6 to the first control circuit whose output depends on diaphragm aperture, exposure time and film speed settings and on scene brightness. If exposure is incorrectly set lights 1 and 2 are unequal in brightness or one of them illuminates steadily and the other flashes. The brightness of lights 1 and 2 is also controlled by a multi-vibrator 9 to 16 which includes a photo-conductive element 16 preferably exposed to the view-finder image. In Fig. 2 (not shown) transistors (18, 19) are connected in series with lights 1 and 2 respectively and a photo-conductive element (17) is connected to the bases of both transistors (18, 19).