iMac Retina 5K Display changes tones when waking from sleep -- Is this normal?

Same issue aswell. It started after a month. Only additional installed software is go pro studio a week ago. I have now uninstalled it.

However problem still exists.

Sleep- waking up without fan- warm beautiful color - fan kicks in- gets bright and yellow.

Any explanation would be helpful to understand whether it is a SW glitch or HW malfunction

Any answers yet? I got mine for christmas and just noticed this issue a few weeks ago and since im on this thing constantly I would have noticed before.

Base Model 3.5 ghz 16gb Ram M290x

I saw this feature from day one so i doubt its due to third party software.

each 5k imac probably has a display profile uploaded at the factory, based on either batch or individual testing, to make the colour temperature and Gamma uniform.

Do you have a recent iphone? see if the colour temperature matches well. apple is making an effort to match the display colours between their products. my iphone 5 is within maybe 100-200kelvin of the colour temperature of the imac.

Since the colour profile is applied via software in the Radeon card, it might take a moment to load each time the computer wakes.

Yes if you plan on doing your own display calibration, this feature is unnecessary, but personally i think you're just creating trouble for negative gain by trying to fight this built in feature.

if you want full control of the display, get an eizo, which costs more than the imac for just the display, and is 25% of the resolution.

Same here for me here as well on a Imac 5k 4.0Ghz/ 16gb /1TB SSD /M295X

Ich have a MacBook 13" Retina on the side and it looks so different/better ! (both have the same software installed)

I`m a little disappointed because this display looks really nice but this yellow/tint and these Fan noises are sh.. even for a first gen product.

Any resolution to this issue yet?

I have the late 2014 model. I understand the model was refreshed in May 2015 so I'd be very interested to know whether the new model has the same issue?

I've spoken to AppleCare 3 times and tried all the usual things, calibrating the colour profile, reinstalled OS X etc and have now had the logic board and screen replaced in this machine to no avail, so clearly this is not an isolated issue. I'm at the point where I want a machine that does not have this issue (I am hoping to get a replacement May 2015 model that is problem free) or I will just ask for a refund.

It's really annoying that Apple never want to acknowledge these issues and we have to try and figure it out ourselves, but at the end of the day while it is not a critical issue that prevents us from using the machine, it is annoying, and we should not have to put up with paying thousands of dollars for a machine that was faulty on arrival with absolutely no acknowledgement of the issue at hand.

I'm glad that Australia's consumer protection laws are on my side with this as Apple are not always very willing to accept fault (iPhone5 camera dead pixels for instance), although I will admit they have been fine so far with trying to resolve this issue.

Still no resolution? Same with my brand new iMac (november 2015) after waking from sleep but also several times a day in normal use. From yellowish to cold blueish and back.

I searched the internet but found no solution.

Anyone knows what it is and what to do about it?

I have the same issue; 5k i7 4GHz; 32GB RAM; 4GB Radeon R9.

I run two displays; a 27" thunderbolt (2012 monitor) with the computer (received 2/2016).

The color is dramatically different; I refer to it as a color temperature. I've run calibration numerous times but no luck with an effective change.

It's extremely distracting when doing illustration and matching colors from one display to another.

Spent hours on chat with apple support, but no luck and they claim that they've not heard of this issue.

I've exchanged the computer once, and new computer performed exactly the same.

I do notice by virtue of having two displays, that when starting up, the color of the Apple logo is bright/blue white on the Thunderbolt, and bright/magenta white on the 5K (you can see it particularly well along the edging of the monitor.

Help with this from Apple would be great, as an illustrator this does impact our workflow.

i just purchased a 2016 21.5" iMac (non-retina) and i have basically the same issue as the OP.

😕