Yes – it is normal – especially if you’re analyzing a clip that is long in legth. Optical flow analysis takes an incredible amount of disk space at times – and you really need to have a lot to even be able to think about doing optical flow retiming.
Optical flow does blow away time remapping in Final Cut – so if you can do it, don’t mind waiting, and have the disk space then it definitely is worth it. The workflow is pretty simple – from final cut right click a clip and send to motion – from there you can set the optical flow parameters and I’m sure you’re familiar with them since you’ve already done them…
BTW, you can set the cache directory that motion uses to store optical flow data in the motion 3 preferences. It’s possible you may have large files there that you don’t need and can delete. Again, these take up a lot of space.
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Paul Escandon
Producer | Director | Editor
Apple Certified Trainer – Final Cut Pro
Oremus Productions
http://www.oremusproductions.com
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Adjunct Professor of Media
John Paul the Great Catholic University