[For After Effects CS5, see "ProRes 4444 and ProRes 422 in After Effects CS5".]
If you use Apple’s new ProRes4444 codec with After Effects CS4 and Final Cut Pro, you may notice a gamma shift (i.e., colors will seem to have too much or too little contrast) when you bring the movies rendered and exported from After Effects back into Final Cut Pro.
To avoid this gamma shift, you’ll need to edit your After Effects CS4 QuickTime gamma rules XML file. This will add the appropriate gamma tag to your QuickTime files on output.
The XML file is found here:
[hard drive]/users/[user name]/Library/Application Support/Adobe/Common/MediacoreQTGammaRulesCS4.xml
Using textedit.app or a similar text editor, add the following line to your MediaCoreQTGammaRulesCS4.xml file:
<QTCodec codec='ap4h' vendor='****' platform='mactel' direction='encode' versionlow='0x00000' versionhigh='*' gammatag='true' />
‘ap4h’ is the 4cc code for ProRes4444. You’ll notice that the XML file already includes entries for ‘apcn’ and ‘apch’. These are the 4cc codes for the older flavors of the ProRes codec.
Once you’ve made this change, you should be able to round-trip ProRes4444 media between Final Cut Pro and After Effects without experiencing a gamma shift.
For more information on preventing color shifts when working with ProRes codecs, see this post:
“ProRes 422 colors in After Effects”
For more information on gamma shifts with QuickTime and Apple software, see this section:
“QuickTime and gamma in non-color-managed projects”
Here’s a thread on the MoGraph forum in which Dan presents the same solution.
(UPDATE: For After Effects CS3, see my response in the first comment below.)