Yellow tinge from bottom to top of the screen, 27" iMac

Good Points. That is the main reason I tell people, If you cannot see the Yellow or Color Variance with browser on Full Screen & in any other Apps, It's A Keeper. The Grey Bar Test shows all the Flaws, especially my Copy & Paste Version. But if you can't see it any other time & you are not a Photographer or Graphic Artist, you will never see the Slight imperfection. I'm not telling people to keep their screens. This is what I'm doing & this is my own individual opinion because I know there are NO Perfect Screens made. I never see Yellow or any difference, so I am happy. But there are some people that will not accept this & I understand their point of view as well. I had 2 iLemons that were unacceptable by my Standards. This one is far better. As Long as I don't use the Grey Bar Test as my Desktop Picture! 🙂

kos, glad you did not get escorted out! 🙂 The reason the 27" look like it is less & more Gradual is because of the larger screen, the bars as further away from one another. Do my Copy & Paste test & you will surely see it is not so gradual & much more drastic. The further away the bars, the less likely to see the difference. But the Copy & Paste Test proves it every time. You notice that someone posted yesterday & today claiming to have a Perfect Screen but we have after I doubted them & asked if they'd do the test, they have never come back. Anyone that claimed perfect screens either was proven wrong or never showed us his Grey Bar Test pictures. There are No Perfect Screens. I even asked all the guys who posted YouTube iMac Unboxing & they all just kind of blew me off & said their's did not have the problem. I know they never tested & they won't. Ignorance Is Bliss! Half the people are in Denial. As Jim Morrison once said, "People Are Strange".

Ok the problem seems to have gotten worse

I was going to hold off for a while but the yellow is staring me in the eyes even on boot

I spoke with apple again today who ask me "Oh it the yellow thing, have you done the firmware upgrade?" at this point i really got pis*ed off and let him have it, he said apple is still investigating. I told him rubbish, it this sort of support that gets to me all saying different things.

CR is calling me tomorrow and i will let them have it too.

He also said their engineer looked at my Mac and said it was ok and within normal range, i asked him if he was blind.

I really dont want a refund as i love this machine apart from the yellow, if i can get one where i cant see other than the test i will be happy but ATM every time i turn this thing on and use it, it reminds me of a japanese smoking room

Guys please tell me if this is normal and acceptable!!!!

http://imgur.com/ri6R7.jpg

http://imgur.com/cEVZ3.jpg

sorry for the rant 😉

rebootnow wrote:
It would be interesting to know their calibration procedure and whether they have changed it at all for these iMac displays.

Hi rebootnow,
It's easy to calibrate iMac using only Mac OS X utilities, but in fact not very accurate.
In the System Preferences > Displays > Color > Calibrate you'll find the Calibration Assistant.
Click on the Expert Mode (yes, yes it's the only way to fine tune the white point).

Then you'll step in a series of 'apples' screen to adjust brightness and contrast (need good eyes and no sunglasses - sorry Florida!).
Then the 'gamma' screen (don't touch this one choose 2.2).

Last is the white point screen.
I push it to 6756 K (don't ask me why I couldn't make it to 6750!).
Save it under a name easy to remember (append the date to the name).
There will be many versions.

It is saved in :
/Library/ColorSync/Profiles/Displays

A file 'yourname.icc' (could be generated once -using a 'colorimeter'- and loaded on every shipping machine).

You can select your new profile in the assistant or return to the default.

You can also edit it in the beautiful 'ColorSync' utility (Applications > Utilities) .
See in the 'Profiles' tab the nice lab plot of the gamut.
You can even compare your calibration with the default in color 3D.
You can drag the corners to spin it in space!!
Hollywood! 🙂

Now the result.
Pushing the white point to 6756 Kelvin the white point chromacity is now
x= 0.950 unchanged
Y=1 unchanged
z=1.127 instead of 1.089

The screen is less warm (slightly icy blue) *and no more pinkish bottom corner*, on my unit.

But the two horizontal grey bars still show a little discrepancy.
No free lunch.

You can try ... it won't harm you iMac.
Cheers!
Jacques.

Message was edited by: Jacques LAPORTE

That's a pretty bad case of the yellows, the bottom right is really pronounced - the genius is truly blind if he says that's within limits.

I see Yellow. Like I said, if you see it with Safari Opened to Full Screen, then it's not acceptable. If you don't see it, then it's a keeper! But if your seeing all the time (that's how my 1st one was), it's not acceptable. It'll drive you crazy. You keep looking in that spot whatever screen your own hoping it will go away. I know. I been there.

I agree - the safari test is probably the best for seeing if the yellow tinge will affect 'real world' use of apps.

Also, I've found these forums to be quite useful. Try scrolling up and down and keeping your eyes focused on a particular post - preferably a shorter one in a white box (like Dino's right above). If you can see it noticeably change colour as you scroll, you've probably got a bad case of the yellows.

Just giving you an update.

If you remember I told you about the email I sent to Apple Corp over my 2nd yellow and loud hard drive iMac i7. I got a call Feb 26th and said a new unit is ordered and Apple will then "test" it to make sure it's a "perfect" machine when I receive it.

It is now March 9th and still nothing. I have been emailing my contact person. They do call back and are very "PRish" (is that a word?). They do not have a clue where it is. Could not even tell me.

Even on my 2nd replacement, I got it within 4 days.

Just wanted to give an update.

Another Great Test is Open Finder & Choose Column View. 2nd Choice. The one with the Blue & White Lines. Either make it full Screen or Drag the Box around your screen, to see the difference in certain areas. For some reason the Yellow shows more with the Blue Bars. Same as CraigsList site.

Thought I'd update everyone from last week. All of our 27" iMacs have arrived, two have the same exact screen and yellow tinge. One is much worse. All are '8009' machines ordered from Amazon.com

One of them has a bit worse yellowing than the others, I snapped a photo with a Canon SLR here:
http://bit.ly/aGjwyZ

This one is 25% worse than the 2 others and we are going to let Amazon replace this one. Icons in the dock look very nice on the left side and rather yellow on the right side. I'd guess this is one of the machines that are particularly poor.

Thanks Jacques. I've used that calibration utility quite a bit.

I was referring to something different though. I'm wondering exactly how Apple calibrates screens in their factory. For example, what part of the screen do they optimize for. Typically it would be the center, but I wonder whether they have started measuring other parts of the screen now that the variability is such an issue.

Hi rebootnow,

I'm sure they have done all the testing already in Cupertino.
With a $250 calibration tool, I can -in my office- make 'spot measurements' of any color on the display for comparison. It takes a few minutes for the grey.

I'm sure (..I hope ..) they have a full report of measures .... maybe for a 'sample' coming out the factory.
Testing a panel means nothing : every panel seems different.

Calibrating the screen won't solve the issue IMHO on a white LEDs backlit display (no RGB LEDs sliders).

But there are a lot of things we do ignore at the moment.
What is the cause of the color shift to yellow.
If it is thermal (a plausible option), is there a way to regulate heat convection without redesigning the device?

They said they have 'addressed' the issue, for me it means they did all they could do.

Cheers!

l

Hi,

just got my 2nd replacement, imac 27 (had 3x 21,5" before with yellow tint) but this one is worst! When the replacement was set up i called apple and told them to postpone my delivery so that I get a newer model.... but unfortunately it is the worst display I ever had. I can see the yellow tinge especially in the middle. I dont have to do the greybar test, i can see it on white background....

I am so pi*sed off, i cannot take it anymore, i will call apple, tell them my opinion and ask for a refund!

I was happy windows user, i was hoping to get a happier mac-user but got totally disappointed, angry & frustrated... will go back to a windows....

regards
diggi

lexvo, it looks like your post got deleted or edited. I read it in my email & of course I agree.