Frequently Asked Questions

What does M.O.S. stand for?

The term �M.O.S.� generally appears on a slate when a scene is filmed without sound.  Hollywood legend defines the term as �Mit Out Sound�.  We�ve heard many fascinating explanations of the term�s origins.

M.O.S. may have originally stood for:

� Mit Out Sound
� Mit Out Sprechen
��Minus Optical Signal
��Minus Optical Sound
��Minus Optical Stripe
��Muted on Screen
��Mute on Sound
��Mic off Stage
��Music on Side
��Motor Only Shot
��Motor Only Sync

M.O.S. A shot or scene filmed without recording sound; an event that, ironically, often seems to throw the sound department into an �Okay-but-you�ll-be-sorry� snit.

Industry mythology has M.O.S. deriving from the request of a long-gone German-speaking director� variously indentified as Erich von Stroheim, Josef von Sternberg, or Ernst Lubitsch� to film a scene �mit out sprechen� (without speaking) or �mit out sound.�

I don�t think so.  There is a less colorful but vastly more plausible origin for M.O.S.: In the early decades of sound, until the 1950s, the sound track was recorded on an optical rather than magnetic track (now always called the �mag track�).  When film was delivered to the lab for processing with a blank sound track, it was noted that it was being send Minus Optical Stripe.  Makes much more sense to me, although I understand the appeal of the apocryphal version.