8bit vs 10bit vs 12bit I do a lot of HEVC encoding and what I've read is 10bit is always better than 8bit, even from an 8bit source, because it avoids rounding errors. Is that true?

Also, then is 12bit better than 10bit or are the rounding errors insignificant at that point?
I can answer your first question. At the same bitrate and transcoding from an 8-bit source 10-bit HEVC is better than 8-bit HEVC, because it hardcodes dither. https://gist.github.com/l4n9th4n9/4459997
I am still unsure, whether that makes 12-bit HEVC transcodes superior  to 10-bit, thats why I ended up here.