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Discussion Starter · #1 ·
Several people here have discussed problems with imovie3. I am interested to know what kind of problems you have experienced and what kind of system you are using with imovie3? Has it been upgraded in anyway?
 

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iMovie 3 has some performance problems, the overall interface is very sluggish compared to iMovie 2.

There also have been various problems with the fonts, titles, filters, and such, but I have yet to witness it myself.

One thing that has bit me in the ass a couple of times is that audio and video easily get out of sync -- not matter how you capture your video, once you export your footage, the audio's sync will slowly degrade with the video over periods longer than approx. 20 -30 minutes.

I've all but stopped using iMovie 3 and am working to move to FinalCut Pro Express now.
 

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Discussion Starter · #3 ·
Thanks for your comments Manny. You are right. I have not experienced any of the so called trouble spots with imovie3 on any of the 3 systems I have. All original mac hardware. I have had the audio sync problem though. I have read in various places that it has to do with the audio bit rate. It is suggested that you make sure your DV cam is set to record tape in 48bit audio. I have also had this when working with video clips copied from DVD's. Someting I found interesting. I ripped two clips of approximately equall length (5 min) from a BadBoys DVD. Imported into imovie3. One clip had the audio extracted while the other did not. Both clips had good audio sync in the timeline. The clip with audio extracted was edited by removing two frames from the audio track and then repositioned and locked to the video track again. No other editing was done. Exported to idvd and burned to disk. The clip with the edited audio track had perfect sync in dvd playback. The clip without editing was out by almost a second. Both clips had audio set to 48 in the export options. Clips ripped from dvd's longer than 5 min are out of sync in the timeline. After retiming, I found that removing 7 frames from the audio tracks of these clips fixed the problem both for playback in the timeline and with the dvd copy. Any comments.
 

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Your camera probably already has 48 bit audio enabled -- as far as I know, most digital camcorders do. Check out your camcorder's manual, they explain the difference between 32 and 48 bit audio and how it works with your cam.
 

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Fall, Sorry for the confusion in my last post; I guess I was not successful in getting my thoughts across because what I wrote is not exactly how it was supposed to come out. Bit rate and sample rate are 2 different things essentially talking about the same thing. Audio quality. bit rate is described in kb/sec. The higher the bit rate, the bigger the file size and the higher quality audio you will get. Most digital cameras if not all can record to miniDV tape in both 12 bit and 16 bit audio. 16 bit audio includes 32, 44.1 and 48kHz smaple rates. 12 bit audio would include sample rates lower then 32kHz. The reason for the 2 recording options with your miniDV camera is that if your are recording audio in 12 bit, there is room left on the tape to make an audio dub. So for example, you could tape your friends racing around the track in thier new sports car with all the engine and tire sounds and then do an audio dub with a microphone over the same segment of tape with your voice introducing each driver. If you have your camera set to 16 bit record, there is no room left for extra audio because of the higher sound quality. Most digital cameras have a menu system that will include record mode. Look in here to adjust the audio record mode between 12 and 16 bit. iMovie3 works much better with video tape made in 16 bit mode because it does not handle dual audio tracks the same way FCP does. My second point was a tie in to something Manny has already pointed out. Clips in the timeline somewhere beyond 5 minutes seem to lose audio sync in iMovie3. I have noticed this with multiple clips I ripped from commercial DVD's. Some DVD's seemed to be worse then others. It might have to do with the way I ripped them or with various copy protection systmes found on different DVD's. At any rate in my case, the audio seemed to alway lag begind the video by about 7 frames. To fix this, I would extract the audio clip to another track, unlock the audio, use maximum clip magnification so that each frame advance in the time line is visible for timing purposes, advance 7 frames in my case, drag the audio clip to reposition it with the video clip, lock audio, export... audio syn. I also demonstrated this by taking two clips of similar length. One clip had the audio extracted while the other did not. After exporting to iDVD and burning to disk, the clip that had the audio extracted was in sync while the other clip was out. Performance in iMovie3 can be improved with the latest update to both iMovie3 and QuickTime. QuickTime is heavily integrated into iMovie3. Also, anything that you can do to improve your system usage of ram or adding ram will greatly improve iMovie3 performance. I have also read that reducing the window size of iMovie3 can improve performance. Hope this is helpful. Good luck and happy shooting.
 
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