So, this is killing me: I can't tell if my screen's ok or not. I get the feeling the bottom left third of the screen is yellower/warmer, but again, maybe I'm just being paranoid. I did all the tests intended for the iMac yellowing, but I can't conclude, maybe my eyes just aren't accustomed to detecting the problem or not. At 80% brightness, iPhone 4 camera: I'm not a photographer or anything, but is my display acceptable? I have AppleCare until August, this was bought secondhand, refurbished.