What does MOS really mean?

I was impressed with the research The Straight Dope put into the origins of OK, not to mention the incredible plausibility of the findings, and am hoping someone could do the same for the term MOS. In filmspeak, MOS is used to denote a shoot for which sound is not recorded. Unfortunately, every film teacher I had in film school (Northwestern [go Wildcats!]) and filmmaker I’ve met in Tinsel Town stubbornly exalts different theories as to the term’s etymology. From what I’ve gathered, the term is either partially in German, mit out sound, or completely in German, mit ohne sound . The first theory sounds ridiculous for including only one German word and the second theory sounds ridiculous for including the German words for “with” and “without” in the same term. Can anyone provide more convincing BS to explain what MOS means and why it is used in American filmmaking? (I realize that I’ve already submitted this thread once before, but it was during the reorganization of the message board, so I never got an answer.)

I’ve no experience myself, but “mit out sound” is correct according to this site.

When I read the title, I was sure you were asking about metal oxide semiconductor. I guess that’s not what you were asking about, though.

Here’s a page with several guesses (such as magnetic optical sound, motor only synch, and music on side): http://www.zoundz.com/MOS_Thread.txt

Some more guesses

MOS comes from “movie ohne Spache” which combines the English slang term “movie” (which was current early in the 1900s when the techology for recording sound on movie film was introduced) and the German words “ohne Sprache” which means without speech.

When sound was introduced, it was primarily so that the audience could hear the speech of the actors rather than read their lines off the screen during brief pauses in the action. Thus, in the minds of contemporary movie makers and goers, what distinguished movies with sound from movies without was the presence or absence of speech, not sound. Hence, “movies without speech” rather than “movies without sound” and “talkies” rather than “soundies.”

I have no evidence at all for anything written above but drewbiehle only asked for “more convincing BS.”

Biblio, some of these are a real hoot. However, as a person with 20 years of Film & Video production experience, I can discount a few of the ones you gave us right off the bat.

M.O.S. is virtually NEVER used off-set.

Minus Optical Signal and Sound are terms used in printing release prints, when the optical sound track is printed next to the frames of film. Does not apply. Ditto with Stripe.

Muted on screen also pertains to projection. Mute on Sound MIGHT be it, since that addresses recording of sound during a take. ( Or, NOT recording ).

Mic off stage, nah. Music on side?? Side of what?? Side salad?? Nah.Motor Only Shot??? What motor? A synch motor? Ahhh now perhaps we are getting somewhere.

In early filmmaking, the camera was not able to hold perfect synch. It was tethered to the sound recording machine , THAT kept perfect 60 hZ cycle synch throughout the take. Perhaps MOS means Motor Only Shot because since there was no sound to go with the take, you could just run the camera motor and not fear being out of synch. I’d buy that in a heartbeat. I don’t think that is it, but I’d but the explanation.

Motor Only Syncis a misnomer. As stated above, you could not HAVE synch back then with just the camera motor. In the 1960’s an onboard crystal synch motor was made available for film cameras. This freed up the camera department from the sound department, and made life easier all around.

The 16mm Arriflex camera I used to shoot my thesis was SUPPOSEDLY using a crystal synch motor. I checked it with a POM ( Peace of Mind ) meter before I left NYC for my shoot. It did NOT indeed hold synch for more than 20 seconds. I had to shoot a documentary on mentally retarded adults , cabled to the sound recorder. Messy…cable was torn out twice by accident.

Anyway, I see it as Motor Only Shot being the best shot. My two cents.

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