Yeah, the camera or print definitely shows a minor colour shift. As I mentioned, that is responsible for part of it but it could not possibly explain all of it, there is simply no way you could get colours that deep and that vivid while also having the most natural skintones (and other colours) that I've ever seen in a Star Wars film. It also varies from shot to shot, even though the camera settings were the same, so its the print that has the tinting in the first place, even if the camera nudged the colours a bit. So like 90% of those colours you are seeing are authentic, and they match other sources too. Even your test pic there looks undersaturated compared to the I.B. print, so the subtle green shift would be almost as noticeable as the photo if it were at comparable levels of intensity; you would also see there is still some pink in the image, which means it needs to be counter-shifted further. I don't think its possible to correct the GOUT to same colour levels because of the fading and the transfer, so you can only get a rough approximation. So anyway, while the screening photos may not be 100% exact, they are the closest to the original colouring that anyone has ever seen, and certainly can be used as a reference of about 90% accuracy IMO, at least in most shots.