10 blade diaphragm shutter aperture calibration f7.5-45, speeds 3/2/1/2/5/25/50/75/100/T/B. Pneumatic release valve. 35mm aperture in screw flange. No 1823. Bausch and Lomb. Volute diaphragm shutter
Taylor Taylor Hobson rapid rectilinear lens F 8.31 inch US 3-256, in 9 bladed diaphragm shutter 3/2/1/2/5/25/50/100/T. Pneumatic release valve, lens number 7823 shutter 3823. Bausch and Lomb diaphragm shutter and lens
