Hi, cjd --

Yes, 8bit output is somewhat limiting, but for much of the kind of work I want to do, it's fine.  So long as I can render out a decently photo-real image, I can play with it in After Effects to match it to a background plate.  I usually render images against a solid green background in Carrara and use AE to key the image into my footage because Carrara's alpha channel is pretty weak.

 

 - Dex