Bell and Howell 35mm film perforation
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35mm Perforation, BH-1866
The 35mm negative perforation has sharp corners, curved sides, a nominal width of 2.79mm and a height of 1.85mm (American National Standard Dimensions for 35mm Motion Picture Film Perforated BH, PH22.93-1974).
Note: This perforation and pitch are used for negative and some special purpose 35mm films.
35mm Perforation, BH-1870
The 35mm negative perforation has sharp corners, curved sides, a nominal width of 2.79 mm and a height of 1.85mm (American National Standard Dimensions for 35mm Motion Picture Film Perforated BH, PH22.93-1974).
Note: This perforation and pitch are used for special purpose and special effects 35mm films.