Sound goes slowly out of sync

First, are the audio sample rates identical? Start there and then we'll try other things. This is not uncommon with separate audio recordings.

I'm sick to death of typing this and ought to keep it as a sticky on my desktop.

Unless your audio recorder is driven by a proper timecode clock, there is no way you are going to keep your recordings in sync. You might get lucky a few times, but that's mostly luck. Even weak batteries in the audio recorder can slow your audio.

but Jim, that's usually not the problem. You may get some drift over the course of an hour, but not enough to account for what many people have been describing.

Make sure all audio is 48k 16bit AIFF. If not, use compressor to convert.

Make sure your easy setup is for the correct frame rate before bringing any aiffs into fcp.

Unless your audio recorder is driven by a proper timecode clock, there is no way you are going to keep your recordings in sync. You might get lucky a few times, but that's mostly luck. Even weak batteries in the audio recorder can slow your audio.

This is only going to result in a tiny drift at worst, even over a long duration. If the recorders are both digital, you're more likely than not to "get lucky." Sample accurate? No. Frame accurate? probably, or at least close enough that nobody will notice. ****, there was no timecode clock on my 16mm camera, just a crystal to govern the motor speed. it never had a problem staying in dead-on sync with either a nagra or a DAT recorder, neither of which had timecode.

If someone is noticing drift, it's probably pretty bad, and it's most likely because of sample or frame rate mismatches.

My question is - How long is the clip, and how far out of sync is it? Karl, If you can give a ballpark number, it should be possible to guess at which kind of problem you have.

One that's bit us repeatedly is having the wrong Easy Setup selected when importing audio into FCP. If the Easy Setup is PAL, for example, but you're working on an NTSC project most things just work fine, but the audio import happens at the PAL frame rate and causes pretty severe drift over time.

Karl,

In the Final Cut Sequence, do you see a green bar across the top of the timeline (where FCP indicates whether things need rendering?).

How long is the program, and how far out of sync is it by the time you get to the end of the program?

-perry

I just finished working on a project shot full 1080p24 with the Nikon D7000. Dual-system audio was recorded onto a Panasonic HVX170 so my workflow was slightly different than yours and I used Compressor instead of Streamclip.

Syncing was easy on all of our shoots except for one day's session. Everything was shot and captured in exactly the same way so I have no explanation. All I did was carefully time the clips and added a slight bit of speed adjustment to the audio. Render. Done.

In Ye Olden Golden Days of Shooting on Film, I learned to shoot a tail slate on anything that was longer than about 6 minutes. The Auricon—and even the Nagra—was capable of changing speed over a long run. If I ever do this stupid film look routine again on the D7000, I shall call for tail slates on longer clips.

In case you don't know, the tail slate is held upside down.

bogiesan

Message was edited by: David Bogie Chq-1