I just returned from an AMC theater in Westminster, CO where they were showing 'Hancock' sourced and projected in 4K on a Sony SRX-R220 on a 50' screen.
Short review: It looked like film. Period.
Embellishment: I have been following the transition from film to digital since the very first shoot-out of JVC's ILA vs DLP in the summer of 1999, when Star Wars was screened on both systems in the Los Angeles area. (Neither were quite ready for prime time.) As a current reference, I saw a DLP presentation of the second Chronicles
franchise at the El Capitan in LA, which is technically an excellent venue, and a 35mm print of WALL-E on a 60' screen at a Harkins Cine Capri near Denver. I would rate the image quality thus:
1) WALL-E. A new print, completely animated, no CGI matting problems, a reference print.
2) Hancock. The projector didn't get in the way. There were no issues with
black level, picture uniformity, pixalization, resolution. Some on this forum will argue that ANSI contrast, MTF and colorimetry are better with DLP, thus a better picture. I would not agree.
3) Chronicles. 2K DLP. Very decent picture.
My first check is for the Previews of Coming Attractions which always appears on a green background. On a DLP pj, it is always 'cartoon' green with white pixels forming the letters. On the Sony is looked exactly as did the film print of WALL-E. Same color and saturation, brightness, no pixels.
The second check is looking at a person's hair. 4K shows more individual strands than 2K. I like that.
The compositing in Hancock was at times very apparent with foreground and background obviously created at different source resolutions. I would image a good film print would look the same way.
The only flaw I could see was a convergence misalignment at the very bottom of the screen where text had the slight blue/yellow halo that plagues every digital cinema PJ I've ever seen. If I had missed the opening and end credits I'm not sure I would have been able to say if it was film or video.
During final credits, with my nose one foot from the screen, I could see the pixels. They are obviously very tiny and don't seem to "flutter" like the mirrors in a DLP unit.
What would 'Hancock' have looked like on a DLP? Don't know. The movie's not that
good to see it again. What will 2K transfers look like on the 4K Sony? Don't know but I'll probably find out since all of the other screens were showing 2K source on 4K units. (I should have wandered into another auditorium and checked it out.)
So, is 4K worth it? Yes. Is LCOS, with some of its inherent limitations, better than DLP at this resolution
? Yes. Will a 4K DLP look better than the Sony? That will take years to find out.
Caveat: I have an Ampro 4600 in my Theater. Not that this would bias my opinion or anything.