MOS

[480sound]

I know this may have been covered many times before; but is there a definitive source for the term MOS?

"Mit Out Sound" isn't a german phrase and "minus optical track" doesn't make any sense.

 

 

 

[Olle Sjostrom]

I thought Mixer Out Smoking was the right one?.  

 

But I guess that makes no sense either; back then you would just probably be smoking on set...

 

Joking aside, could it be this abbreviation, If even, could've come from another country and just sticked? The Wikipedia page is pretty funny:

 

https://en.m.wikipedia.org/wiki/MOS_(filmmaking)

 

[PMC]

Good one Olle. 

 

I heard from old guys it stood for, "mit out spreken." With out speaking so there is no need to roll sound. 

 

Of course I am now old and repeating the definition. 

[axel]

I once heard it stood for "motor only sync", but do not know myself what the meaning could be. 

[Alien]

MOS was originally motor only sync. Years ago in the olden days.....

sync was made by machines being powered by 3 phase motors. Sound would be recorded on 35mm film then later 35mm magnetic. Interlock would be done with sound starting the first phase then camera joining on then the next 2 phases would be powered up and the machines would all roll in sync. If there was no sound to be recorded then sound would keep their recorder offline but still powerup the interlock system and roll the camera. If you go to the older stages at Pinewood you can see a small room about 15 feet up on the side of one of the walls. This use to be the sound room where the 35mm recorder would be kept and the whole interlock system controlled from. There also use to be a bus set up so that this could all be done on location.

[Matthias Richter]

I learned: 

 

minus optical sound 

[stacysound]

Back in the early to mid-70s my father was a sound man. His experience was post, and production sound. He told me that it meant “Minus Optical Sound”.

 

Interested to see what the other veterans have to say.

[Izen Ears]

Heh, I thought it was Minus Optical Stripe!  As in, the edge of film where optical sound lived.

 

I love Motor Only Sync, that sounds like a synth band!

 

Dan Izen