I'm helping a friend edit some video shot 6 years ago with his Canon Optura. It was originally transferred to VHS without a hitch, and capturing the original DV tape with iMovie HD seems to work — until you go to export to iDVD where the audio ends up out of sync. Original audio was captured at 16 bit, not 12, so that's not the problem. We've tried capturing the audio to a separate track, and that didn't work. My understanding is that iMovie 8 is even worse.

Before we get more frustrated with this, does anyone know if we might have the same problem with Final Cut Express? This is about an hour distilled down to 36 minutes. Suggestions?

FCE is just Pro scaled back, so you're probably less likely to have the problem. I've only really used FCP and Premiere Pro, and I've never had any sync issues.

sync problems are usually the result of poor performing hard drives or a slow processor. Make sure the project is on an external drive. Make sure no other apps are running.

External drive? I've made sure that nothing else is running. We are doing this on a month old 24" iMac, the top one, and there is a ton of drive space, but I'm willing to give the external drive a shot.

A couple of Canon's first gen DV cameras sampled sound at 48.048 kHz instead of 48.000 kHz. This causes audio sync problems.

If you can find some old threads on this problem, there may be an easy solution. You may need a good sound editor application to repair the sync problem. In quiet areas of the recording, cut out a few samples every so often and filter the transition so there won't be a "pop" or "click."

Complaints on the Apple Discussions board seem to point to iDVD 08. Loading an earlier version or using Toast with a .mov file worked for some people.

You shouldn't need an external drive on a month-old iMac. Everything should be fast enough (although there could be a conflict if RAM is tight).

Even though the computer and technically the drive is fast enough, digital video yields the best performance when the System/Apps drive is DIFFERENT than the one that has the data/clips. This may not be your problem, but it's worth a try.

quote:

Originally posted by Phyllis Evans:
External drive? I've made sure that nothing else is running. We are doing this on a month old 24" iMac, the top one, and there is a ton of drive space, but I'm willing to give the external drive a shot.

Extract the audio without altering the sample rate. A good sound editor will tell you if the sample rate is the problem. If the sample rate is not exactly 48.000 kHz, that's at least part of the problem.

iMovie 8 HD could be part of the problem also.

Chuck, I think you may have hit it on the head. The camera is older than I thought, and that may be the problem.

We tried importing a small clip from the camera (original tape) into FCE this morning. I did just a couple of small edits, exported to QT movie, then used Toast to burn a test DVD. Sync problem was just as bad. I have the file that was edited in iMovie HD 6, and I'm going to try exporting the audio, redoing it with QT Pro, then drop it back in and see what happens. More later. Oh, and John is now looking at newer Canons.

Make certain about the sample rate before proceeding elsewhere. Open the audio file in Quicktime Player Pro. Determine the sample rate using Command-I (Movie Info).

Here's an example with a sample rate of 44.100 kHz.

I happen to like Canon camcorders for a lot of reasons. I just don't like new HDV Canons, which is to say I don't like the HDV specification. So, unless your friend needs a pseudo hi-def camcorder, he should wait to buy. I think you can correct the sample rate problem in software.

quote:

Originally posted by Terry White:
Even though the computer and technically the drive is fast enough, digital video yields the best performance when the System/Apps drive is DIFFERENT than the one that has the data/clips. This may not be your problem, but it's worth a try.

Terry,
Why is that?

You want video on a drive for video only, preferrably with just a few projects per drive. You don't want video files interleaved - head seek latency becomes too great for smooth operation, and can lead to other more serious problems.

Therefore, unless you've got money & time to burn, a removable hard drive is very helpful. Store every project on a removable drive. And if you're really, really, really super smart, you'll backup the movie project on yet another removable drive.

Well, it looks like the problem was with the camera encoding. I grabbed the sound track with QT Pro, resaved it as an AIFF, dropped it back in and deleted the original audio, and it seems to have made the transition to DVD without the lag. My sincere thanks to all of you.

I love this board! And our great MacGroup people.

Terry, Chuck,
With the notion that I should put my data/clips on a drive separate than my
hard drive that houses the apps I will be using to manipulate all this data...
I ran into a glitch right from the start.

Importing the clips from my camera connected to the computer, to the external hard drive yielded a show-stopper. Frames were dropping out immediately. When iMovie should have read "importing" it was reading "camera playing." I've never
run into this with all the projects I've created.

So I stopped the process, had the camera import to my internal hard-drive,
no problems. OK, so if I continue with the thought process of the data/clips
being on a separate external drive, I could manually copy these clips over and then work with them, but with the experience that this process 'fails' from even the import process, there's no confidence that frames won't be falling out as I
work from the hard drive to the external drive.

It makes a big difference as to what system you are using and what the connection is to the other drive - in addition to the hardware used for the other drive. I wouldn't agree that you should *always* use a different drive from the app drive, but certainly the potential is there for better throughput with the right hardware setup.

An external drive, unless connected via eSATA, is almost always going to be slower. Firewire 800, the fastest non-eSATA connection for externals, is still much slower than any eSATA or even an IDE internal. Anything less than FW800 is going to be painfully slow.

Well, I don't have the 'deep pockets' system.

The connection IS thru my FW 800 port. The external drive
is the previous internal drive that used to be in my laptop
until I upgraded to a larger drive.

I'll continue to use the process that works.
I don't have time for dropped frames.