Some FCP filters are 8-bit. Some auxiliary image processing software is 8-bit. strypes can recite a long list. Subjecting a really 10-bit project -- one shot or generated in 10-bit -- to an 8-bit process sacrifices the anti-banding advantage of 10-bits.
I think there's a way to mitigate this damage. Raise the [display] gamma of the original 10-bit from 2.2 to 3.33. Be sure to use a 10-bit process for this! Now use the nasty 8-bit process. Then convert the output back to 10-bits (if necessary) and finally reduce the [display] gamma back to 2.2 (using a 10-bit process again).
This trick is based on [display] gamma 3.33 being the best fit to the Hecht requirements for invisible luminance steps.
Dennis Couzin
Berlin, Germany
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