Original Effects Cleaned up with the help of AI...????

[Metryq]

Then cut to the original effect at the last moment so the fade is preserved.

Ugh! I don't think so. I find it disruptive enough watching the dissolves in older movies where there's a "pop" in the image just as the dissolve begins. (This was done to shorten the number of frames needed for the optical effect, rather than running both shots, before and after the dissolve, in full length. The "pop" is some minor mismatch in grain, exposure, etc. The lab may have done everything exactly by the numbers, but even minor variations in every batch of film stock can make the difference. They ran into a lot of that during the making of TRON due to the high contrast processing.)

If the original footage is still available... we're still talking about a lot of processing work for what potential economic gain? TOS re-re-re-release, the Dissolves Edition!

 

[Tosk]

The "pop" is some minor mismatch in grain, exposure, etc.

There was no way around it in the old days. A dissolve was an optical effect, so the two shots that actually dissolve into each other were one generation down from the film on either side.

 

[Maurice]

Yep. Part of the reason you can spot the difference just before a dissolve is that the dissolve is an optical printer effect that's spliced in, and the difference in grain, opacity, etc. in those frames snap in and out at the head and tail of the dissolve.