I do not think there is any reason Disney would use a film source if they ever do a 4K upscale of II or III.
On another note, RoTS generally has a very good reputation for its picture quality on BD. II less so, but I think the original master is probably of low quality, as an early digital film. A TPM scan might look better to some of us here, since the Bluray release was handled pretty poorly. Presumably Disney would use the negatives.
You’re most likely right in this particular case. It would be great if Disney/Lucasfilm went back and compared the two masters, as I’m sure that there is a film master along with a digital one as well.
There is a great article written in Film & Video about the filming of Episode III, and the technical process that the Sony Cameras were apart of at the time. Reading it now seems very primitive to say the least.
My question is, how will this footage hold up over time when compared to material shot on digital now (2016)?
Digital today seems much more life like than Episode II & III, at least it does to me.