Never heard of it and noticed it with my new 50ST50. Especially noticeable when the scene has bright white (gray) against a dark background (likes others have mentioned). Watched "The Artist" last night, and it was like peering thru a prism for me - the same with "Blade Runner" too. By the way, off center it is less obvious. Sadly, the Blu-Ray picture quality is beautiful, but the ABL, and this rainbow effect is very annoying. Just needed to mention, my wife does not see it. Go figure?