The Dark Knight, wasn't completely filmed in IMAX, only select scenes. And those are presented in 1.78:1 (IMAX screens are very close to square, so even 16:9 is a cropped frame) while the rest of the film is 2.40:1. So the black bars appear and disappear, sometimes very briefly. I found this to be distracting. Also the 35mm footage has edge enhancement applied so there are some halos or rings around areas of medium-high contrast.
The picture issues, while minor, keep this disc from being rated as a Tier 0 title though.
I heard that a lot, but the switching never bothered me. I was too fixed on the visual impact of the Imax scenes. I never noticed the halos, but I have not done a critical viewing in some time. I may go back and look for that.
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