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

+2
i am completely confused by the camera issue as i had posted last.

Should we believe in the camera?

Lucky you, my iMac is from the same week but with a production number in the low 4000s. It's better than before but not acceptable.

My workplace has a dozen last gen 24in iMacs. None of them show this problem. So much for IPS technology! Last time I checked more advanced meant better, perhaps Apple have a different dictionary.

rickstervt wrote:
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.

I see what you mean.
Color perception seems quite subjective and contextual.
When I boot up my unit there is a grey screen before the Apple logo which is absolutely uniform grey (to my eyes).
That's why I bought a colorimeter, to measure the colors from the screen with an apparatus not my eyes.

They're all built in China. I have heard this from numerous sources including Apple. Maybe the ram is inserted here for those that say Assembled in the USA.

pug1334 wrote:
They're all built in China. I have heard this from numerous sources including Apple. Maybe the ram is inserted here for those that say Assembled in the USA.

I wold love to see some clarification on this. I also thought they were all built in China.

I have some confidence that it was at least assembled here (even if the parts are sourced from China). It is a week 12 model, so they wouldn't have any time to build it in China, then send it to Union City, then send it to me. Also, there are many factory designations (like ones for Korea, Taiwan, Freemont). Why would they have those if they were all made in China?

Here are the first 5 digits: QP012

rickstervt wrote:
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.

See this site comparing a “Samsung LED-backlit monitor” and a “Macbook CCFL-backlit display”.
Go figure!

http://alex.mullr.net/blog/2010/01/led-vs-ccfl/

2-3 days FedEx from Shanghai to my door in past

Seamus Foley wrote:
Lucky you, my iMac is from the same week but with a production number in the low 4000s. It's better than before but not acceptable.

Happy here with my i7 iMac purchased 5 months ago... 🙂

Built=Assembled, not Manufactured.

*from stridemat of macrumors forums:*
In addition to "W8" for China (Shanghai), other manufacturing location codes include:

F, FC, XA, XB, QP, G8 (USA)
RN (Mexico)
CK (Ireland)
SG, E (Singapore)
MB (Malaysia)
PT, CY (Korea)
EE, QT, UV (Taiwan)
1C, 4H, W8, YM, VM, WQ, 7J (China)
RM (Refurbished/Remanufactured)

rickstervt wrote:
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.

I think this has to do with colors being washed out because of the high brightness of the screen. That is also the reason the yellow tinge is most visible on a grey background.

Suppose a yellow tinted gray spot on the screen has RGB values of 50%, 50%, 45% (normal medium gray is 50%, 50%, 50%).

When the same spot should display (yellow tinted) white, these values would be 100%, 100%, 95%. (Normal white is 100%, 100%, 100%). However if the brightness is cranked up, the values of 95% for blue will also be 100%.

Of course, just my theory 🙂

Viewing a word document, the yellow/warmer cast is easily seen when moving the window from the upper left to the lower right. Same with Finder.

Second iMac, still yellow. I asked the Apple Genius there to check this one after he did the defect test on my old one which took 30 minutes. Since the test took too long, I asked him just to look at this one and he said this one looked great! Not so great, still yellow. I'll keep you all posted.

A few additional details would be informative and helpful: 1) order date, 2) production week, 3) screen image, if possible, and 4) was this machine purchased online or taken from store inventory. Thanks.

I'm not sure how to get the production week or anything but I can tell you I bought this in the apple store.