Comparison photometer, possibly home made. Split field comparison. Direct vision through circular step wedge, blue tint, calibrated, 0, 10, 100, 1000, 1:10, 1:100, 1:1000. Mirror reflects illulmination from disc with step wedge, calibrated 160, 250, 400, 600, 1000, lit by small bulb. Powered by flat battery (Ever ready pat. 24008/08) through press switch and rheostat adjusted by screw from exterior of case. MEter connected across lamp. Calibrations for f/4.5 and 16sch. Table in Swedish giving shutter speeds for photometer settings.