sorry - assumed this was well known - go to
and fill in as much as you can - I included this thread/discussion so they could see it wasn't just me..
good luck and apologies for my assumption..
I'm having the same issue, can't believe there is not a fix. Just spent over $3K on a MBP retina and it looks horrible on my external monitor, calibrated twice to no avail. I have an AOC monitor which worked perfectly with my older MBP.
Everything looks very washed out, like someone left on a greeny blue light on in there.
I used to work in Apple's Software Test dept years ago, they would have tested lots of external monitors - and decided not to fix it for the release.