June 25, 2018 at 4:29PM

0

Audio drifting out of sync after 3-5 seconds, premiere pro.

Hey NFS,

I recently shot a conference where I had a locked down camera running with a scratch audio(A), another camera(B) with no scratch and a stereo condensor running off the sound system.

I used plural eyes to sync my audio with the A camera that ran scratch, and brought it into premiere. I turned off "drift" in the settings, but the first time when this was on - it was still drifting out of sync. My timecodes were slightly off, so not helping, but I can work off one point on the footage and get the B camera footage synced to the audio then off sync about 3-5 seconds later.

All the video was recorded at at 23.976, my sequence is 23.976 but the B camera seems to be off.

Source Audio is 48000 khz, 24bit mono
Project is 48000 hz, 32bit floating point mono. (is this the problem? I'm not sure how to change the project bit rate)

A camera:
Type: MPEG Movie
Image Size: 1920 x 1080
Frame Rate: 23.976
Source Audio Format: 48000 Hz - 16 bit - Stereo
Project Audio Format: 48000 Hz - 32 bit floating point - Stereo
Pixel Aspect Ratio: 1.0

B camera:
Type: RED R3D Raw File
Image Size: 3840 x 2160
Frame Rate: 23.976
Pixel Aspect Ratio: 1.0

2 Comments

After chatting with someone, it seems like the best option is to speed the B camera up, to match the audio. There was no option on my little zoom h5 to record at 23.976 fps, is this the problem? I know for sure the B camera was recording at the right speed, but it's completely off. And the audio matches what came off the A perfectly.

June 25, 2018 at 9:26PM

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Nate Brown
Director, Art Director
95

I've been syncing hours of video with recorded "wild sound" for the past 10 years using the "track stretch" feature in the Vegas Pro editor. All you have to do with Vegas is sync the start of your long audio track, then jump to the end of your audio track and "stretch" the audio to match with the video track, then export everything with a high quality "editing" CODEC. ( I use the Cineform CODEC to export )

If it's a multi-cam shoot, then I base everything on one video track as the "master" track, then stretch both the audio and the other video tracks to sync with the "master" track, and then export all of the different video tracks with a high quality "editing" CODEC. It's pretty easy to do, though you may find some of your cameras are out of sync by as much as half a frame, which is fine as long as you stick with one audio track for everything.

July 5, 2018 at 4:49PM, Edited July 5, 4:51PM

1
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Guy McLoughlin
Video Producer
32687

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