Harmy said:

And now imagine what kind of detail level could be achieved if they did a proper 4K scan of the original negative, when even a poor 1080p scan of the o-neg, that doesn't actually resolve much beyond 720p, can show more detail than a 4K scan of a projection print.

I wish that could still be done. This was taken from a recent article about the rediscovery of Black Angel, the short film originally shown before ESB:

Tanaka: I remember when we were working on the Star Wars restoration, that was a different process. I think we optically recreated interpositives. But in order to do this, it went through some kind of warm chemical bath cleansing. The weird thing about Star Wars was that it was made up of different film stocks, so it went through this bath and they didn’t know what would come out on the other end...

Parker: You mean if it would survive or not? ‘George we might destroy your entire film, but it’s... we think it’s going to be OK.’

Tanaka: There’s a space battle shot and a close-up on Hans Solo, and the original negative is coming out of this cleaning solution and it’s just acetate.

Parker: It’s all clear. Oh no, did the bath dissolve it?

Tanaka: Yeah, it dissolved it, depending on the film stock.

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