[tig] Syncing from Audio CD

Marc Wielage mfw
Wed Apr 7 04:03:17 BST 2004


On 4/6/04 3:43 PM, "Knox McCormac" <knox at optimus.com> commented on the TIG
list:

> The original recording device at the shoot was a laptop. I was told that the
> audio was recorded directly to the laptop into a wav file.  The person I was
> talking to had no idea what software the sound company was using or if there
> was any external hardware involved. So there are no original field DAT's or
> anything with a timing reference. The wav files were then copied to a CD and
> sent to us. 
>--------------------------------snip----------------------------------<


Man, if that's the case, all bets are off.  To my knowledge, there's no
easy, reliable way to record location sound locked to code by using a laptop
alone in the field.  This has been discussed many times on the Usenet
newsgroup rec.arts.movies.production.sound.

If the files are .WAV files with embedded timecode (created from ProTools or
the equivalent), you have a fighting chance.  But it's still sounds like a
non-standard system.  If they used a Deva, Fostex, or one of the new Sound
Devices or HHB machines, it can work, assuming you have a compatible
playback device (like a Fostex DV-40).

Get hold of the production sound recordist and ask them if they've ever done
this before.  My guess is no, and that they had a bad reference in the
field, which would lead to a small timing error (like the 8 frames per three
minutes you cite).  Given that, the solution is to transfer all the film
MOS, and then use ProTools -- or another varispeed device -- to manually
expand or compress each take back into sync.  The good news is, there's a
chance that the sync drift is constant and repeatable, meaning once you find
the precise varispeed percentage, the editor can apply it to every take and
it "should" work.

A production crew doing this kind of stuff without a timecode slate, no
notes, and no contacts for the post house to is almost unforgivable.  The
clients sound like real amateurs -- not that being an amateur is wrong, but
I get mighty peeved when filmmakers like this don't ask the right questions
questions and make tests BEFORE they shoot.

You ever notice how 90% of the major problems in telecine are all related to
audio and timecode -- never color?  <shaking my head in frustration>

--Marc Wielage
  LA colorist-at-large







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