[LAU] SMPTE timecode?

[philicorda]

On Thu, 2010-02-18 at 18:24 +0100, Florian Faber wrote:
> Rick,
> 
> >    I've been told by a local friend that it's not worth the trouble.  Video 
> > is approx 30 FPS, and audio is 48k S/s, so alignment 'by ear' is 'good 
> > enough'.  That may be what they're planning to do anyway...
> 
> If you have a drift between video clock and your sample word clock of as
> little as 0.01%, it means you have an offset of 360ms (or ~11 frames)
> per hour. Which you can only 'fix' by src, and you don't want that.

The way I have done this in the past is to make a DVD with all the music
in the correct places, and also to provide the music as wav files.

Then they can see where you intend the music to be, and how it works
with the picture.

It's very unlikely that they will leave the audio in the exact place you
decided to put it anyway, as you are not making the final cut. So in
practice the important part is that your vision is communicated in an
understandable way.

> 
> Just to give you an impression how bad it really can be: In real life I
> have encountered word clocks ranging from 47981Hz (=-0.03%) to 48041Hz
> (=+0.08%) when syncing to video gear.
> 
> Unless your goal is to make short clips (3-4min each, and adjust the
> offset each time), you are knee-deep in trouble without syncing your
> clocks. Forget about the timecode, you make the offset adjustment only once.
> 
> OTOH you might just be lucky and have equipment that doesn't drift that
> much :)
> 
> 
> Flo