This is what you get when you try to cram a 3D and 2D version onto the same disc. You run out of space and have to lower the bit rate for the 3D bits so the 2D image suffers. I too have noticed it going from a perfectly clean crisp image to "grain"; though it isn't grain, it's digital noise and compression artefacts. Some bits look waxy too. I wonder what the iTunes and other digital versions look like? Considering they're just 2D and don't have the 3D version in the same file. Unless they just got given the same transfer to work with which wouldn't shock me.
I've just watched my new Dredd BD in 3D and would say it's most definitely the worst PQ in my collection (by far), very disappointing (watching on 51" calibrated plasma via ps3). I'm not saying the director adding grain wasn't the case, but comparing the grain on some of my other BDs, to the noise seen in Dredd, I would bet it's simply more due to a poor transfer. (or someone simply needs to show whomever's in charge, how to do it so it doesn't detract from the film)
Going off 1 viewing, there were times when I questioned whether I had a faulty disc (as sometimes the picture was so bad), but a quick search proves it's not just me thinking my eyesight's starting to go. The quick edit fight scene between the two judges on the catwalk, was so jarring as 1 second it was super sharp, then .5 a second later it cuts to something resembling a worn out VHS recording, taped LP using a cheap pack of blank tapes bought from the local garage! (if this were 2 decades ago)
When SD DVDS of low budget 80's horror films (on a regular dvd player) look noticeably better than a 2013 BD release of a new film, you know somethings dodgy. Especially as the US version handled by Lionsgate, has been given high marks by a number of well known sites
I may have 'obtained' this previously via certain nefarious digital means (not saying I did...), and if I did, it (may have significantly) looked better than this official copy. I don't know whether i'll bother watching it again in 2D tbh, and I certainly wouldn't recommend this version to anyone or be using it as demo material. Great film though!
Dredd was released by Entertainment in Video in the UK, its no surprise there is problems with the picture quality. I stopped buying Blu rays released by EIV since they released the Underworld blu rays which have crap PQ but the US versions which are done by Sony have excellent PQ. Entertainment in Video have a track record with doing poor quality Blu rays.
It's not a low budget flick at all, HRH. It had a very healthy $50M budget.
I've watched the blu-ray in both 2D and 3D and can definitely say the 3D is the "cleaner" of the two methods. The blue digital noise in dark shadow is still there in one or two scenes (most notable under chins, funnily enough) but the highest of the high quality scenes are phenomenal. The slo-mo scenes are quite ethereal in their beauty.