Sync Drift

We have a Mac Pro with Final Cut Pro 7. WE had 16 mm film and 1/4 tape converted digitally. We are syncing up the sound with picture. The specs for the picture (that were returned to us) are 720 x 486 and the 1/4 tape is at 48 kz. It requires rendering and is not close to being in sync. We get serious sync drift. When we submit our film and sound what should we be requesting for specs? Thank you for your help. Allyson

What did the transfer house send you back? Videotape? What format? Quicktime files? What ? er. Okay, I guess my question for both is "What format?"

If the film ran at 24 and the tape or files you got back were at 29.97 with pulldown or 23.976, then you're going to have to do an audio pulldown to conform your sound. It's been a looooong time since I had to do that, but I think Cinema Tools will do it for you. I know Soundtrack Pro can. It's lossless and instantaneous; it just changes the audio rate from 48 to 47.somelongnumber so it syncs. There's a slight pitch change, but it's really hard to notice unless you do an A/B comparison.

That wouldn't cause serious sync drift, though, so if that's not it, then I'm back to wanting more info, if you please.

>I know Soundtrack Pro can.

The pulldown options are on the front panel. I'd think it can do a better job than CTs (and without a pitch shift). I just couldn't get it to export the right audio duration after the slowdown was done. I think I was missing a step somewhere.

It's not really instantaneous in STP, as STP would ideally resample the audio to playback at the correct speed at 48khz. CTs changes the flag on the QT movie so it plays back slower, hence the 47.somelongnumber.



www.strypesinpost.com

Thank you for your response, but...

We tried going to Sound Track Pro but we do not know how to use the software program.
Before you answer perhaps we can give you the specs that were returned to us from FotoKem.

We submitted our 16mm film to be transfered to a digi beta (4.3) full frame. What was returned to us was a video track with the following specs: 720x486; 29.97; 10bit uncompressed; 4:2:2.

We also submitted 1/4" audio tape which was transferred in ProTools at FotoKem.We received back an audio mono track 01. wave; 140.6 K/sec; 48.0 KHz; 24 bit integer.

We know the timeline settings have to match the 720x486 format, but when we try to change the settings we get the following message: "Codec not found. You may be using a compression type without the corresponding hardware card." Help. This is really Greek.