Respectfully, please remember that this is a problem that can develop gradually over time. So if you haven't had your mac for ~2 years and if it's not a 2014 rImac, *please* point that out if you reply. Your new Mac can have retention but realistically it just hasn't had time to develop yet, or perhaps you don't use dark blue/black interfaces (like photoshop, sublime or solarized dark theme in whatever app) enough to notice white on blue/grey burnin.
My 2014 rImac had really bad image retention. It developed over time and got worse and worse.
I'm getting it fixed now. My fear is that the new panel will also have retention and this time, break after my applecare is out, leaving me out to dry. Maybe like 80% of rImacs have this problem and I exacerbated it because I use my iMac *a lot* and also the retention is mostly noticeable when you switch to a dark screen and since a lot of users probably dont do this often they might not notice they have this problem.
Please also know that you might not even *know* that you have image retention because a lot of the times it is only visible on dark blue or grey screens, NOT black.
To test if your screen has retention of light on blue/grey colors:
1. open this image http://i.imgur.com/5D5q6JL.png and set it to your background on a different space, so that you are ready to switch over to this space to investigate the intensity of the burn in
2. now open 2 tabs of safari, https://www.washingtonpost.com/ and http://www.nytimes.com/ and leave them for 30 seconds to 5 minutes depending on how intensely you want to test. Basically, just open up enough tabs to fill your ENTIRE screen (or as much as possible) with a WHITE background and BLACK text
3. Ok after that's been up for 30 seconds to 5 minutes, switch over to the desktop space with the blue background and inspect your panel. When I first noticed the problem on my panel it was very subtle and I had to look very closely. After just several months, just about anything, including the red apple in macrumor's logo, would burn in very noticeably even after 30 seconds of exposure. So take a good hard look.
My 2014 rImac had really bad image retention. It developed over time and got worse and worse.
I'm getting it fixed now. My fear is that the new panel will also have retention and this time, break after my applecare is out, leaving me out to dry. Maybe like 80% of rImacs have this problem and I exacerbated it because I use my iMac *a lot* and also the retention is mostly noticeable when you switch to a dark screen and since a lot of users probably dont do this often they might not notice they have this problem.
Please also know that you might not even *know* that you have image retention because a lot of the times it is only visible on dark blue or grey screens, NOT black.
To test if your screen has retention of light on blue/grey colors:
1. open this image http://i.imgur.com/5D5q6JL.png and set it to your background on a different space, so that you are ready to switch over to this space to investigate the intensity of the burn in
2. now open 2 tabs of safari, https://www.washingtonpost.com/ and http://www.nytimes.com/ and leave them for 30 seconds to 5 minutes depending on how intensely you want to test. Basically, just open up enough tabs to fill your ENTIRE screen (or as much as possible) with a WHITE background and BLACK text
3. Ok after that's been up for 30 seconds to 5 minutes, switch over to the desktop space with the blue background and inspect your panel. When I first noticed the problem on my panel it was very subtle and I had to look very closely. After just several months, just about anything, including the red apple in macrumor's logo, would burn in very noticeably even after 30 seconds of exposure. So take a good hard look.
