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cinol

macrumors newbie
Original poster
Sep 29, 2010
7
0
Hello,

I've been plagued by the yellow tinge and some nasty flickering on my iMac 27", in an effort to make it obvious for the Apple staff during repair I created a desktop image that shows the problems fairly clearly. While my file is not very helpful in showing the yellow tinge problem, it revealed a weird pattern contamination problem that appears to affect all 27" iMacs.

The staff at the local Apple store tested all their 27" and they all have the same problem. They assure me that the problem is software and will be addressed by a future firmware/software update. The problem doesn't seem to affect any 21" iMacs, we did not test the new cinema display. It's worth mentioning that this file did clearly demonstrate just how many iMac displays are faulty in one way or another, even in the Apple store itself, it looks like these displays are highly inconsistent.

So I am sharing the file here to accomplish two things:

- Verify that ALL 27" have the same problem
- Motivate Apple to resolve this problem quickly

screen_test.tiff

It's an uncompressed 11meg TIFF image, set it as your desktop image to see it fullscreen.

For the curious: my "repaired" iMac display still has some yellow tinge to it but less, it also has darker bands at the bottom but also mild...hey, it doesn't flicker anymore!

I am sad to say that the general trend amongst iMac buyers is to try to find one "that you can live with" as opposed to finding one that lives up to Apple's marketing claims. Selling quality durable hardware is no longer profitable if you can "satisfy" your customers by being real nice about taking your computer away for 7 days only to replace the faulty part with another faulty part, over and over until they get tired of it and lower their standards to "what they can live with".
 
I am sad also…

I am sad to say that the general trend amongst iMac buyers is to try to find one "that you can live with" as opposed to finding one that lives up to Apple's marketing claims. Selling quality durable hardware is no longer profitable if you can "satisfy" your customers by being real nice about taking your computer away for 7 days only to replace the faulty part with another faulty part, over and over until they get tired of it and lower their standards to "what they can live with".[/QUOTE]

You're SO RIGHT! I bought an iMac 21,5" i5, 3.6 on August and I'M STILL WAITING for a GOOD ONE. It will be the second replacement, after 2 previous bad quality iMac. Both of them had yellow screen issue (so strong for one of them that a client ask me if I put a yellow gradient on his picture!), one had flickering display (Xmas tree) also, the second had hard disk issue.
I lost so many times calling technical support and costumer service, sending back computers, waiting FedEx… I'm tired and mostly unhappy regarding my first expectations on legendary Apple Macintosh quality ! On my concern, Apple does not give you anymore the SUPER QUALITY it should. I don't know what I can expect from the third iMac I will have, but surely, if this one is not perfect I will ask for total refund. I refuse to keep a new iMac "that you can live with" not for this high cost!
Due to my recent experience with Apple I think their control quality standards are seriously going down. Well, I guess they don't mind, they have so many costumers now, one more or one less satisfy, that is not important to them.
 
I can Verify that ALL 27" do not have the same problem, just tested mine and no problem here.
 
I am sad to say that the general trend amongst iMac buyers is to try to find one "that you can live with" as opposed to finding one that lives up to Apple's marketing claims. Selling quality durable hardware is no longer profitable if you can "satisfy" your customers by being real nice about taking your computer away for 7 days only to replace the faulty part with another faulty part, over and over until they get tired of it and lower their standards to "what they can live with".

You're SO RIGHT! I bought an iMac 21,5" i5, 3.6 on August and I'M STILL WAITING for a GOOD ONE. It will be the second replacement, after 2 previous bad quality iMac. Both of them had yellow screen issue (so strong for one of them that a client ask me if I put a yellow gradient on his picture!), one had flickering display (Xmas tree) also, the second had hard disk issue.
I lost so many times calling technical support and costumer service, sending back computers, waiting FedEx… I'm tired and mostly unhappy regarding my first expectations on legendary Apple Macintosh quality ! On my concern, Apple does not give you anymore the SUPER QUALITY it should. I don't know what I can expect from the third iMac I will have, but surely, if this one is not perfect I will ask for total refund. I refuse to keep a new iMac "that you can live with" not for this high cost!
Due to my recent experience with Apple I think their control quality standards are seriously going down. Well, I guess they don't mind, they have so many costumers now, one more or one less satisfy, that is not important to them.[/QUOTE]

Let us know how is your replacement. Cheers
 
I can Verify that ALL 27" do not have the same problem, just tested mine and no problem here.

That's very interesting! Which iMac is it? Is your operating system and firmware up to date?

I have:
iMac 27" i5 (2.66GHz)
ATI Radeon HD 4850 (EFI driver 01.00.383)
Mac OS 10.6.4 Build 10F569

If this matches what you have then it can't be software.

Let me know.
 
Hello,

I've been plagued by the yellow tinge and some nasty flickering on my iMac 27", in an effort to make it obvious for the Apple staff during repair I created a desktop image that shows the problems fairly clearly. While my file is not very helpful in showing the yellow tinge problem, it revealed a weird pattern contamination problem that appears to affect all 27" iMacs.

The staff at the local Apple store tested all their 27" and they all have the same problem. They assure me that the problem is software and will be addressed by a future firmware/software update. The problem doesn't seem to affect any 21" iMacs, we did not test the new cinema display. It's worth mentioning that this file did clearly demonstrate just how many iMac displays are faulty in one way or another, even in the Apple store itself, it looks like these displays are highly inconsistent.

So I am sharing the file here to accomplish two things:

- Verify that ALL 27" have the same problem
- Motivate Apple to resolve this problem quickly

screen_test.tiff

It's an uncompressed 11meg TIFF image, set it as your desktop image to see it fullscreen.

For the curious: my "repaired" iMac display still has some yellow tinge to it but less, it also has darker bands at the bottom but also mild...hey, it doesn't flicker anymore!

I am sad to say that the general trend amongst iMac buyers is to try to find one "that you can live with" as opposed to finding one that lives up to Apple's marketing claims. Selling quality durable hardware is no longer profitable if you can "satisfy" your customers by being real nice about taking your computer away for 7 days only to replace the faulty part with another faulty part, over and over until they get tired of it and lower their standards to "what they can live with".

No problem here on my i7 27-inch (mid-2010). And I do know my yellow screens well... this being my seventh 27-inch after returning four late-2009 and two mid-2010 iMacs.... all for yellowing issues.
 
Shrug...

Hello,

I've been plagued by the yellow tinge and some nasty flickering on my iMac 27", in an effort to make it obvious for the Apple staff during repair I created a desktop image that shows the problems fairly clearly. While my file is not very helpful in showing the yellow tinge problem, it revealed a weird pattern contamination problem that appears to affect all 27" iMacs.

The staff at the local Apple store tested all their 27" and they all have the same problem. They assure me that the problem is software and will be addressed by a future firmware/software update. The problem doesn't seem to affect any 21" iMacs, we did not test the new cinema display. It's worth mentioning that this file did clearly demonstrate just how many iMac displays are faulty in one way or another, even in the Apple store itself, it looks like these displays are highly inconsistent.

So I am sharing the file here to accomplish two things:

- Verify that ALL 27" have the same problem
- Motivate Apple to resolve this problem quickly

screen_test.tiff

It's an uncompressed 11meg TIFF image, set it as your desktop image to see it fullscreen.

For the curious: my "repaired" iMac display still has some yellow tinge to it but less, it also has darker bands at the bottom but also mild...hey, it doesn't flicker anymore!

I am sad to say that the general trend amongst iMac buyers is to try to find one "that you can live with" as opposed to finding one that lives up to Apple's marketing claims. Selling quality durable hardware is no longer profitable if you can "satisfy" your customers by being real nice about taking your computer away for 7 days only to replace the faulty part with another faulty part, over and over until they get tired of it and lower their standards to "what they can live with".

I downloaded the file as described and looked at it. I don't have the issues you are describing but I don't doubt that you are experiencing them.

With all the posts I see about yellow, or flickering, or dog whistles I count myself lucky.
 
More details

Well I'm baffled by all the people who claim not to have this problem, I personally tried 4 different iMacs and they all had it.

Note that for the problem to be observable, the file should be viewed at Actual Size (or 100%) and full screen or in a big window.

The pattern is most visible in the blue square and looks like a 2px checkerboard pattern of darker and lighter blue. It's really quiet obvious to me but you may have to look closely, 2 out of 3 geniuses could not see it in the brightly lit store, but the genius admin saw it immediately on all of her iMacs.
 
that could have something to do with peoples isight , its like the test for color blind people , some people can see very well and see a slight difference in colors while others would not even notice if the blue would be a checkered blue and green on their display
same for flickering some people can even make out a slight flicker others will just not notice it
and it has not only to do with the eyes itself , our brain makes things up so if the eye doesn't see something or sees something that doesnt fit the brain is completing the picture if you understand what i mean
sorry a optician could explain that better
but its a fact that a lot of people have no hundred percent isight and would need glasses , but they think they dont need them because they still can see their 27" imac in front of them on their desk
 
I see the issue in the "solid blue" squares, but not the flickering, unless the image is being moved around the screen.

-Iamthinking
 
That's very interesting! Which iMac is it? Is your operating system and firmware up to date?

I have:
iMac 27" i5 (2.66GHz)
ATI Radeon HD 4850 (EFI driver 01.00.383)
Mac OS 10.6.4 Build 10F569

If this matches what you have then it can't be software.

Let me know.

iMac 27" 2.93 GHz intel core i7
ATI Radeon HD 5750 (EFI Driver Version: 01.00.417)
Mac OS X 10.6.4 (10F2056)

I've not seen any of the reported yellow tint screens in person, and I've seen quite a few 27"ers now, the initial reports put me off upgrading to the 27" but after a friend got one and I had a play about with it I decided that I should (post recent update) the reports on this forum would put me off from buying, it seems that over 50% of people have had bad experiences with the 27" :(
 
ongoing problem

I have had an iMac for two years now, and I am a photographer doing serious time in this machine, so when the screen was a mess I got Apple to replace it. This was not easy; it took a lot of hassle. The better screen that I finally got has at least a stop of density shift from left to right and dim vague bands are visible. When I put two identical images side-by-side, the one on the right always has more density and contrast. This has never been a suitable screen for professional photography, though the software and computer itself have been fine. Frankly I have been surprised that their reputation for making the object itself slickly done did not apply to these screens, and from what I read here they are not getting much better. The obvious solution is to get the smaller iMac and use its screen as a primary screen for files and documents and day to day business, and add a second screen that is purchased to be a good graphic arts monitor. For the price the iMac is still a nice machine, and the phone-in advisors are often very good. Does anyone know what an affordable, quality monitor to use for proofing fine art photography and book dummy files might be?
 
News from Apple

Hello,

So I just got a call from Apple to tell me that the pattern bleed problem is not software after all and is in fact caused by the video card (ATI Radeon HD 4850).

They will be replacing the video card.

So to all of you ATI Radeon HD 4850 iMac owners out there, you might want to check yours for pattern bleed.

Cheers
 
I have an i7 model with the 4850. I suspected my video card is a bit at fault. I notice subtle flickering when booting the computer up during the gray screen and initial desktop screens for both windows and osx. Also, when loading windows, I get this nasty flickering of black on the screen for a second or two. In the last couple of months I've also been getting cpu hangs when full screening video from time to time, rather it be flash videos on the web or vlc videos. I only get the hangs when in the process of fullscreening.

As for the blue flicker square, I can't see any noticeable flickering when looking directly at it, only when looking to the side of it. I can see the checkerboard pattern in both the lower squares, as well as a slight difference in color between the top left and bottom right corners-- but I already knew my display had a slight bit of yellowing. Maybe I can use this to convince them to get me a free upgrade to a mobility 5850 iMac.
 
I have a mid 2010 i5 quad 27". I ran your test, found no yellowing cornering and no flickering. The solid blue box does have a very light dotted pattern on native resolution. If you zoom in further, the pattern disappears. Also, i took a screen cap of the dotted solid blue to see it up close. The strange thing is, if you move your test image half way down the screen (in a window when you can see the dotted solids, and align the screen cap of the solid blue half way intersecting your test pic and 1/2 way out of it, you'll notice the dots only affect the portion that's within your test pic. This is also true if you observe the screen cap of the solid blue block by itself and moving the test image above and below the screen cap.. seems like the test image plays a role in affects solid colors at certin resolutions
 
I have mid 2010 i3 and it's blue on the top side and yellow on the bottom.
more yellow problem that I have is for 1-2 seconds after wake up the computer from sleep.
 
I just looked at the test file and it confirms I have a very decent screen so they are out there...
However, I have had a few exchanges until I finally received a good screen.


Good luck in finding a suitable display.
 
refurbed 27" i7 4850 here, and no issues with the test except slight yellowing in the bottom right-hand corner.

However, I don't know if anyone has noticed this, but the yellowing decreases quite a bit if I lower my line of sight to view that corner straight on.

Also, that same corner has pretty bad flashlighting. I don't know if that's related to the yellowing or not.

I think these are all typical symptoms of LCD panel manufacturing inconsistencies. The complaints I've read in this forum are very similar to the complaints in the HDTV forums I frequent. Finding the "perfect" LCD HDTV panel is extremely hit or miss also.

I understand how frustrating this must be for some people. Because my computing needs aren't visually exacting I'm going to live with the slight yellowing and flashlighting and be happy I don't have stuck or dead pixels, a loud hard drive, etc.

btw, not sure why but the flashlighting seems to decrease when I crank the brightness up all the way for a few seconds then decrease it all the way, then return it viewing level... Also seems to decrease the yellowing a bit but it may just be an optical illusion since it's so slight anyway.
 
I do not see a pronounced flicker on mine. I have a gray bar / banding on the bottom, but no screen flicker that I can tell.
 
Got my i7 4 days ago.
I honestly think it's nearly perfect since there's no yellow tinge, no pitched screen noise, no loud fan/hd.
Had to install Switchresx to get the proper resolution on the Cintiq 20WSX due to a compatibility issue with the MDP.
Only thing is that I notice the backlight bleed when the iMac screen it's "turned off", but apart from that I can't see any other screen issue during daily work nor I can say my screen has something wrong.

Anyway, I downloaded the test image and I can see the flicker and the dots on both blue and grey rectangles.
I repeat, I belong to those who don't notice anything wrong during daily work.

But if you tell me those are symptoms of a faulty graphic card which could get worse AND Apple recognizes it's a serious issue, I could send it back.

My choices are:
- have the whole iMac replaced (got to decide before tuesday)
- get just the display replaced during next weeks
- live with it and get the diplay replaced when it eventually gets worse

Any suggestion?
Thanks in advance.
 
I can Verify that ALL 27" do not have the same problem, just tested mine and no problem here.

Neither do most peoples. As always, this is the internet forum people come to complain at every time they get a bad one making it look like there are TONS of problems out there when in reality the number is very very few.

No offense to you OP, I'm sorry to hear you have a problem but these threads are a dime a dozen.
 
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