Let's start at the beginning:
How are the captures created?
Is there any compression happening following scanning?
Has any manipulation occurred following scanning?
What colour space is being used?
When doing the comparison screen caps, what software are you using? This is important, as...
Thank you, RAH, for bringing empirical analysis back into the conversation. Screencaps are useless in this type of analysis, for the reasons cited above, as well as that we don't know the methodology by which the captures were obtained, resulting in subjective "well I think this looks better"...
RAH left one other factor in appearance to the end that may not have been picked up on: certain theatre chains will deliberately underrun their xenon lamps in a futile attempt to stretch bulb life, resulting in a dim image on the screen. This has been going on for years, and if you think it...