I'm working on a shot with a bunch of Rotoshapes, and when I preview the final composite in the Flipbook, everything looks fine, but when I render a Disk Flipbook or FileOut (rendering to uncompressed 10-bit SD, no fields), there are certain frames of the render where parts of the Rotoshape "slips" or jumps in a way that does not show up in the standard Flipbook render. When I step through the shot in the Shake frame by frame everything looks fine...all the Rotoshapes are perfect, All of my proxy modes are set to "Base", so it's not a render quality issue.
What's up with that? Any help is appreciated.