AOTC and ROTS were shot end-to-end digitally and therefore don’t have any natural grain structure on the negative. What you probably noticed in theaters is print grain.

That said, TPM has been heavily DNRd and at least AOTC has also been DNRd somewhat to remove digital noise.

For TPM, there’s Schorman’s HDTV preservation. It’s essentially an HD version of the same transfer on the DVD, meaning there are issues like oversharpening artifacts, a pink color tint and a more closely cropped picture. You essentially have to pick your poison here, and most people think the current transfer looks better, despite the DNR. We probably won’t get anything that truly replaces the official release unless someone manages to scan a film print at 4K.

For AOTC, Schorman’s HDTV preservation is quite good. It looks less DNRd to my eyes and has better colors, but it’s also lower bitrate than the official releases.

For ROTS, you’re not going to find anything that looks better than the official 4K release, but Schorman’s release might have more accurate colors.

Hope that helps.