Robbie's advice is for editing in Premiere only. That will not work for After Effects.
From Dave LaRonde:
Dave's Stock Answer #1:
If the footage you imported into AE is any kind of the following -- footage in an HDV acquisition codec, MPEG1, MPEG2, mp4, m2t, H.261 or H.264 -- you need to convert it to a different codec.
These kinds of footage use temporal, or interframe compression. They have keyframes at regular intervals, containing complete frame information. However, the frames in between do NOT have complete information. Interframe codecs toss out duplicated information.
In order to maintain peak rendering efficiency, AE needs complete information for each and every frame. But because these kinds of footage contain only partial information, AE freaks out, resulting in a wide variety of problems.
So edit in Premiere than output it as a type of file that does not use Interframe compression. It's been discussed fairly often on the AE forum and people have suggested a few different things, such as Quicktime using the PNG codec.
So, when it comes to using your HD footage in AE and you've got questions, chances are someone else has asked it. So come on over to the AE forums and search on there.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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