DescriptionOptical-film-soundtrack.svg Two methods of recording sound onto film. "Movietone" Variable density (left) and "RCA Photophore" Variable width
Description35mm film format with opticalsoundtrack-fr.svg Français : Format de la pellicule de cinéma 35 mm avec son optique. Date 21 March 2010 Source
Description35mm film format with opticalsoundtrack-ru.svg Русский: 35-мм киноплёнка с оптической звуковой дорожкой Date 21 March 2010 Source This vector
Description35mm film format with opticalsoundtrack-HE.svg 35mm film format with opticalsoundtrack Date 11 August 2010 Source Own work after File:35mm film format