I have made some tests. I rendered the same fragment of video from After Effects in three different ways.
– Apple ProRes HQ
– Uncompress 10 bit YUV (preserving RGB)
– Uncompress 10 bit YUV (without preserving RGB)
When I reimport them to the AE cs5 I see no difference with the originals in AE, and no difference between them.
When I open them in quicktime player 10.0 I see the apple pro res HQ a little brighter than the original in the AE Viewer, and both Uncompressed 10 bit YUV (preserving and not preserving RGB) quite darker.
Now I’m completely lost.