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

sgrecco wrote:
Hi!

My monitor is 2232bw.
That's the point. I have NEVER seen the color variation while in full screen (except when the image was black - a very known problem with LCDs). Another point that we MUST consider is the viewing angle. While in the iMac it is huge (178 degrees), in the common LCDs it is shorter; and the camera may be sensitive to it (the same way a camcorder can capture the refresh rate of a monitor and the human eye can't).

Backlight on the 2232 is CCFL (source Samsung).

You are right about the viewing angle.
The Dino's rule of thumb : if you can't see it full screen then it's a keeper, is a golden rule.

Cheers!

lexvo wrote:

If this screen is good in real life, then maybe the camera wasn't perfect straight towards the screen. Some LCD screens show color and/or brightness variation when viewed from an angle. The solution is to take a picture from the screen with:
1) the camera straight towards the screen as good as possible
2) with the camera further away from the screen (and zooming in): this will lessen the angle the screen is viewed from

Good point lexvo,
It seems you must have a good camera and a tripod.
If the lens and the panel are not parallel and far enough from each other, color variations that does not exist on the screen are captured by the camera (artifacts).
But that is subtle, IMO.
The bottom could be darker but it can't put a yellow zone on the right (at least in the tests, I have made with my Lumix).
If someone with a good cam could give a try ?

Cheers!

The strange thing I've discovered about this yellow screen issue is that when I'm playing games and there is a white completely white screen, it seems there is absoulutely no yellow. Even when you do the tests on the squeaked site for the dead pixels and the test gets to the white screen there is no yellow at all. Could it be software after all? Probably not but you would think yellow is yellow on any white background or screen. Try it.

To add on to the previous reply about no yellow in a white backgound while gaming, try also going to the dashboard. Look at the weather widget... "White clouds" Move the widget in the area where the yellow tinge is know... The clouds remain white!

Just an observation!

BB

+1
I also noticed that but can't explain it...

I'm moving this post from the 27" iMac flicker thread to this one since it the flicker issues are effectively solved. I received a week 7 27" iMac in early February. It had yellow tinge as well as a gray bar across the bottom of the screen. In addition, it wouldn't boot from the startup disk and airport didn't work.

I had the screen replaced (although they didn't replace the screen cables) but the new screen had the same gray bar and worse yellow tinge. I've posted images of both screens at http://www.designeq.com/imac/

A few days later they replaced the logic board (and strangely, replaced the LCD cables that should have been done on the first repair) but this did not fix the airport problem (or the screen problem). The install disk seemed to be a bad disk and when I got a replacement, it did boot from that.

I sent 3 messages to my Apple Senior Adviser, apprising him of the issue and asking how to proceed, but he completely ignored them and never got back to me.

I finally called AppleCare today and got another adviser, who apologized for the problem, said a machine this new should not have had those problems and offered, without any prompting on my part, to replace the iMac.

I told him I had misgivings since people are still reporting yellow tinge issues on this forum, but I really don't have much choice as I need to get wireless to work.

Most of my interactions with Apple have been pretty good, but having a senior adviser tell me at the beginning "We'll do what it takes to make things right" and then ignoring all my attempts to contact him, left a bad taste in my mouth, along with wasting several weeks.

I will report on how the new machine looks when I get it.

Apple has stopped anymore replacements with my 3rd iMac.

It’s not “perfect” (I know there isn’t any perfect screens out there), but it’s certainly better than the previous two. It does have a completely silent hard drive. No. 2 constantly grumbled.

It also has a very small dirt speck in the bottom right and only noticeable in a white screen.

I posted before about dead pixels but that was a mistake. I had some “tacky finger” stuff on my fingers when I took it out of the box and got on the screen. Wiped it off and no dead pixels.

The yellow is still but only noticeable with the Dino test. One thing I noticed about this 3rd replacement is the Airport is faster. That’s nice.

So I am embracing this iMac, trying to forget it’s flaws, and beginning to enjoy it.

Later.

SuperLorenz wrote:
Why did you wait so long between the replacements ?
I'm waiting my first iMac 27'' replacement, Apple told me that the pre-screening process takes a long time but I need it to do my job....

I didn't. I returned the first defective iMac within 10 days, it was Apple that took 2 months to supply the replacement defective iMac (It occurred during the fabled production halt).

BTW, I don't believe viewing a full screen in white is an adequate test. The gradient is gradual and the brain has difficulty processing that on the scale of the screen. It is immediately obvious when comparing smaller separate windows with white backgrounds.

Ultimately, I think the most important criteria is how the display looks and performs in actual everyday use across a variety of user specific activities. The tests some of us are performing with gray bars with a camera, for example, are not always conforming to what we actually see. My 30" ACD did not "pass" the gray bar test, but even after being aware of that I have trouble actually seeing the gradients. So I am going back to enjoying my current display and computer. And I plan on ordering a 27" iMac within the next two weeks.

I just drove the 100 mile round trip to my nearest Apple Store in Madison, Wisconsin to pick up my replacement i7. Recall, that my first was a week 46 with a subtle case of the yellow tinge and approximately 20 dead pixels in the iSight camera. Ten days ago, The Apple Geniuses replaced that machines display with another yellow tinged display that was supposed to be from the new "batch" of "fixed" screens which we now know is a load of BS. I promptly rejected that display and the store ordered me a brand new machine. That machine is now sitting on my desk at home and looking every bit, if not more flawed than my very first machine. This unit has a much more prominent dark linear shadow that runs almost completely across the bottom of the display about an inch and a-half from the bottom edge. There is also the yellow tinting that is notable with the naked eye. I took colorimeter measurements. There is approximately a 600K white point difference from the right side of the screen to the left side. The right side being warmer.

Do I just suck it up and accept it as it is, or demand a refund? That is the only thing left to decide now. I am leaning towards keeping it and possibly buying a second display, once the newer generation Cinema Displays come out and are deemed "safe" to buy.

<Edited by Host>

I also have the yellow tinge problem but I am wondering if I should just deal with it because it's not that bad. I only noticed it because I was reading up on it and came across this problem. Also, I've read that many people who sent theirs back only received and even more defective one. I would have never noticed it if I had never read it. Should I keep it or no? I'm still quite impressed with the display and the hardrive only grumbles at startup which I assume is normal when booting up.

Ok I am back with what appears to be great news!

I have a good iMac and it's free of the YELLOW TINGE. I decided to swap my iMac out from a different Apple Store. It paid off. There is still a slight color variance, but I can live with that! Being yellow free is a dream. I have crisp white pages! I am so excited... Finally.

Folks don't give up!

Name: iMac Intel (mid 2009)
Group1: iMac
Group2: Intel
Generation: 7
ModelCode: imac mid09
CPU speed: 2.66GHz
Screen size: 27 inch
Memory - number of slots: 4
Factory: W8 (Shanghai China)
External link: Technical specifications by apple-history.com
External link: Repair guide by iFixit
Model introduced: 2009
Production year: 2010
Production week: 09 (March)
Production number: 16478 (within this week)
Uitbreidingen: Uitbreidingsmogelijkheden van dit apparaat

Forgot to also include my display information from the color sync utility. I will continue to monitor my display, no pun intended... hopefully it will not appear out of nowhere. I can finally depart from this thread... OMG, I kinda feel like the guy who crossed the picket line at the moment... VICTORY!

Manufacturer - 00000610

Model - 00009CB5

SN - 00000000

Manufacture Date - C67AE380

finally someone here is actually saying what I have been saying for months now, but since its me no one pays mind but instead they listen to sgrecco, well, I would say to many others not satisfied get a refund, if you see it only with the grey bar, and not with normal desktop use, then keep it, if you could live with it. Another thing is, digital cameras are sensitive to any variation just like film is. And for those who are going to wait, I will wait because the next iMac more likely would have 3.0 usb ports, and we would have slow mo ports, I would wait for those iMac with 3.0 ports that have 5 gigabyte data transfer.

Well that's a ray of optimism!

I have a week 12 iMac arriving on Friday. I have had 5 iMacs so far, all with a tinge. Hopefully my sixth will be my last (in a good way, not in the "accept it or refund" way). The unique thing is that this iMac is coming from Union City, California rather than Shanghai! I can also confirm that this one is built in the USA, with the serial starting with QP (not W8).

Will the USA built iMac be any better than my China built iMac? Tune in on Friday to find out!