David.Austin.Allen wrote:
Image persistence is user caused, so I doubt that the Apple warranty covers it.
This is just pure foolishness. An LCD screen will not show image persistence after a mere hour or two with a static image. This problem is endemic to the 24" iMac and is caused by excessive heating behind the display. The image persistence can be fixed by simply changing the desktop background to pure white and leaving it sit like that for several hours. You can pretty much remove the problem in the future by using SMC fan control and running the fan speeds up to around 2000 RPM or so. The persistence isn't damaging the screen, but it is indicative of a design flaw due to the obsessiveness with Apple over keeping the computer as quiet as possible. Under normal use in a cool-ish room, the problem will not usually show up. If you are making heavy use of your iMac (like using Photoshop or doing video editing), you'll start to see this problem crop up. If you regularly push your computer like this so that the internal temps often run hot, you definitely need SMC fan control to run the fan speeds up.
My iMac has had this problem more frequently as the computer has aged. I suspect the continuing build-up of dust in the fans and vents causes higher temps on a regular basis which leads to this issue more frequently. One of these days, I'll have to open the thing up and clean it out. I never saw this problem for the first year or so that I had the computer.