Audio and Video out of sync after capture

Hi:

This is a new problem--I just captured footage off a 60-min mini-dv tape--using capture now--and when I play it back in the canvas (w/o having moved it into the timeline) the audio goes of sync with the video about half-way through the clip.

Why is this and how do I solve it? I have been capturing other footage for this project with the same format, same camera and have had no problem. When I play the footage back off of tape on the camera, its fine.

What gives?

Also, all of my footage--including from this tape--is a little wonky, meaning bleeps, blips and waves in the footage. Audio is set to 16 bit, capture and sequence settings match...I don't know what the problem is here. Again, never had this one either.

Can anyone help on either account? BTW, I'm working with FCP Studio 2.

Thanks!

Nicolle

First off, it's not a great idea to capture an hour's worth of footage in one clip. It is done, but it's not a good practice. Sync drift is precisely one of the big issues when you do this.

It could be bad tape, it could be a slow or misformatted drive, it could be you're running other applications that are taxing system resources or interfering with the capture process (eg. antivirus). The fact that you say your tape has "wonky" bits would also suggest that the tape is either damaged or recorded in LP mode.

Use the OSD function on your deck or camera and check the tape's recording mode. If it's not LP mode, try capturing in 10-minute chunks and see if the problem goes away.

Also, you know you're not supposed to judge sync in the Canvas if you have External Video turned on, right?


www.derekmok.com

are your audio and video playback methods matched? if audio is set to built-in and video is set to firewire (or any other mistmatch) that almost always results in sync issues.

though based on your OTHER issues, there may be other things afoot...

Didn't know about Capture Now not being a good idea. I was told it was the easiest and best way to capture footage where you might be using a lot of what you shot.

It seems unlikely that the prob. is the tape--I just went through all of my clips--which translate to a clip per tape--and now it seems this audio lag is happening on ALL of the clips, as well as the "wonkiness" I described.

Its not LP, I recorded in SP.

What is OSD mode on the camera? I shot on a Canon XL 1 and am importing on a Sony consumer DCR-HC 21.

How can I tell if my LaCie Drive is misformatted? Having an apple, I didn't need to do any formatting when I connected it to my MacBook.

Could the prob. be FCP?

Thanks for your help!

Yes, I have considered this. Right now audio playback is set to default. At one point, I changed it to built-in, then I changed it back. The option for firewire is greyed out. What to do?

Nicolle

So, now I tried capturing 10 min. of footage using the canon camera and when I playback the footage is out of sync from the get-go, as well as wonky.

I also adjusted my audio playback setting to firewire.

What is going on here?

Nicolle

> Didn't know about Capture Now not being a good idea. I was told it was the easiest and best
> way to capture footage where you might be using a lot of what you shot

Whoever told you this doesn't work on feature films. Capture Now is a less reliable way because if it fails 55 minutes into a one-hour capture, you don't get anything to show for it. Capture Now is faster than logging, but logging is far superior. I'm not saying you can't ever use Capture Now; I'm just saying it's not the preferred way to do it. It's a quickie method that works in some cases, is indeed the only option on rare occasions. But "best way" -- absolutely not.

> How can I tell if my LaCie Drive is misformatted? Having an apple, I didn't need to do any
> formatting when I connected it to my MacBook.

Depending on where you bought the drive, it may not be formatted for Mac OS. Mac OS can read PC-formatted drives, but there are some bad restrictions -- FAT32-formatted drives have a 2GB upper limit to file sizes, which can mangle captures. Always format your drive for Mac OS Extended before using it.

That said, I don't believe that's your issue (though certainly worth checking). Did you already check on Wayne's point? Set your External Playback to "Digital Cineam Desktop - Main" and "Built-In Audio" and check the sync that way. If you're playing sound out to the camera, you can't judge sync on the Canvas -- you have to look on the camera's LCD screen and listen to sound there as well, or connect a monitor/TV to the camera and watch the picture there. The Canvas and FireWire-playback sound will never match up.

Check all drives connected to your system. Is any drive over 90 per cent full? That's a killer.

One last thing: When capturing from a DV tape, sometimes you can get "digital hits" from the field recording that can cause your entire capture to go out of sync. Rare, but I've seen it several times over the years. Try pushing the In point of the problem clip a little later and see if there's any improvement. If you see "distortions" on your captured clip, capture the same section a second time and see if those hits are at the same spot. Try logging your clip around the damaged area and see if it works.

Yeah, this is really tedious troubleshooting work. It's unfortunate that this problem has about 30,000 potential causes.

Oh, and list your software versions and hardware specs. We could spot things in there, such as crossed FCP/QuickTime/OS versions that can cause bugs.


www.derekmok.com

My capture now was reset to limit capture to 65 min, so the 55 limit was not an issue.

I checked my LaCie--its formatted for Mac OS Extended.

My video and audio playback are set to the default settings--firewire for vid and default for audio. Playback is happening via my MacBook--no external monitors or speakers.

This afternoon I tried capturing diff. footage in 5-10 min. chunks and sync was just fine.

I think the "wonkiness"--the bleeps, blips, ripples, etc--might have to do with the camera I shot it on. When I play the footage back in the camera, its this way, too. I shot with a Canon XL 1, 16 bit audio.

I checked this footage against some other footage I shot with my Sony DCR and this looked mostly fine--though there were a few bleeps and blips.

In any case, with the Canon footage, there are so many bleeps and blips to work around--I don't know if capturing around them will work, but I will try it.

One thing I to note at the start of this problem re. the capture now process was, I would come back after capture now was completed to an active capture window saying "searching for media" and/or "searching for time-code break"--though the tape had come to an end and there shouldn't have been any time-code break 'cause I never rewound the camera during recording. It seems to make sense that this might be connected to the sync issue.

Also, I wrote back in July re. 12 bit Audio Hell--the bleeps and blips I'm getting now from the Canon footage seems...similar (not as heavy) to this problem even though since then, I've been shooting on the Canon at 16 bit.

What do you think?

And oh, yeah, my specs:

brand spankin' new (end of June) MacBook Pro
Mac OS X: 10.4.10
FCP 6.0 Studio 2 Suite
QT 7.2.0
LaCie 250 GB with OS Extended

All new--no drives taxed.

Any other ideas?

well, i think thats your biggest problem. just letting the capture now roll on beyond the end of the tape. its a FAR, FAR better idea to log clips rather that simply "dummy-capture" a whole tape. for reasons derek mentioned and a ton more.

i think:

1. you are creating you own problems, following some questionable initial advice
2. your old XL1 may be petering out...