Original sentence: ", and so this was noted as a joke on the production reports and the camera slates for the shot.A popular (presumed to be mythical) origin theory is that MOS stands for either the German "Mit ohne Sprechen" or its broken-English counterpart "Mit out sound", that is, "Without sound" as a 1920s German-émigré director might have said it.The actual power source for the camera motor was in the sound booth.The director responded "Mit out Sprechen.The procedure acquired the name "motor only shot", thus MOS.The recordist would start the camera motor without starting the matching "sound" motor and electronics.When a shot was planned that did not require sound, the sound mixer would ask the recordist to "roll the motor only"
Edited sentence: " The Recordist would start the camera motor without starting the matching "sound" motor and electronics.",  and so this was noted as a joke on the production reports and the camera slates for the shot.A popular (presumed to be mythical) origin is that MOS stands for either "Mit Out Sprechen" or "Mit Out Sound," a broken-English phrasing meaning "Without sound," as a 1920s German-émigré director might have said it.The actual power source for the camera motor was in the Sound Booth.The director responded "Mit Out Sprechen.The procedure acquired the name "Motor Only Shot", thus MOS.This myth ignores the fact that in German the word for "without" is "ohne"; it is highly improbable that a person speaking German as his first language would mistakenly say "mit out" for "without".When a shot was planned that did not require sound, the Sound Mixer would ask the Recordist to, "Roll the Motor Only