"I've never seen this before" - iMac 27 inch horizontal bands.

[Kabir8]

So I sent out my first yellow tinged iMac a week ago.
Replacement arrived today.
The SECOND I turned on the screen on the brand new machine today, I noticed a problem.


There is better color uniformity, and yellowing doesn't seem to be the issue except for this huge horizontal gray band across the bottom that is very prominent.

I talked to the Apple Senior engineer who had "never seen this issue before", and was surprised since I had one of the newest serial numbers he has seen (week 10 iMac i7)

Attached is the picture I sent to Apple which has earned me an advanced replacement (machine sent to me while I keep the defective one until I receive the new one - then have 10 days to return the old one or I get charged for 2)

(Ignore the vertical reflections, the horizontal bar where the dock lies is the issue at hand here)

Image is straight from my Canon with no retouching at all.

[JimKirk]

All mine did.

Nothing you can do about it.

[Kabir8]

You're telling me a senior engineer says he has never seen the issue to this extent, and all of them have it?

My old iMac did not have this issue, it was yellow with two VERTICAL bands that were more visible at angled viewing.

But this is just plain as day. It's a dark shadow, and I don't want it to worsen over the years if it looks like this 1 minute out of the box.

[definitive]

my early 2009 has something similar when it comes out of sleep. i get a line towards the bottom of the screen (more visible on left side) and one towards the top. they're both about four inches tall, and after about 5 minutes they go away when the screen has "warmed up"

[Kabir8]

My screen has been in use for around 4 hours in and out of sleep, and the line looks very prominent with no signs of fading, unfortunately. I will of course keep a close eye on this.

[mac-matt]

i wanna get one but all these screen problems are making me second guess myself and thinking about waiting until everything is good to go

[wessew]

Kabir8, I have a calibrated display. I can see some blotchiness to your screen and the faint vertical banding but I cannot see the grey horizontal band. Your screen looks pretty good relative to the ones I have seen with yellowing and backlight intrusion on the Apple discussion boards.

[Kabir8]

Originally Posted by wessew

Kabir8, I have a calibrated display. I can see some blotchiness to your screen and the faint vertical banding but I cannot see the grey horizontal band. Your screen looks pretty good relative to the ones I have seen with yellowing and backlight intrusion on the Apple discussion boards.

Calibrated display? What model?


My screen is MUCH better than my first. Yellowing is not noticeable, blotchiness, I can live with, but its definitely there.

However, the vertical bands that you may see are probably the door behind me and shadows from the walls. The horizontal line is plain as day, I'm surprised you don't see it, I sent it over to the Apple engineer and he definitely saw it and told me I shouldn't have to keep the machine.

I told him: "I Don't know what to do now, what would you do?" and he suggested I get another replacement.

View it full size, its one inch up from the bottom of the screen spanning the entire width of the monitor. Granted, with color I cannot notice it, but any light color, and it reveals itself.

[Pachang]

Every 27" iMac I have seen (about 5) have had this problem to some extent.
They all have a dark band across the bottom of the screen

[WilliamG]

Originally Posted by wessew

Kabir8, I have a calibrated display. I can see some blotchiness to your screen and the faint vertical banding but I cannot see the grey horizontal band.

Wha? You seriously can't see the horizontal bar at the bottom? That's crazy talk!

[Btom]

Originally Posted by WilliamG

Wha? You seriously can't see the horizontal bar at the bottom? That's crazy talk!

I did have a look at the screen with the Photoshop. There is a ~5% darker stripe along the low edge of the screen. Also, the low right quadrant is slightly yellowish (RGB=97,107,108) and top left corner slightly bluish (RGB=90,100,110).

I can see also reflection of the photographer (slightly below half hight, a little bit to the left) and the reflection of a medium side picture (around centerline, close to the left edge).

To really assess screen quality one have to take this type of picture in a dark, black room (yes, dark, and painted mat black) and also provide a reference picture of a neutral gray target, placed in the same area of the frame, and taken with the same camera, as the screen shot (I know, it is quite a lot to ask for).

I am just wondering how bad was the first screen?

Tom B.

[Kabir8]

The first machine was noticeably yellow and completely unacceptable.

This machine is not as yellow (though I notice it is still present) but this gray bar is too much. Watching a movie, I was able to see the gray bar affect the image on the screen without having to look that hard.

The shot I took was taken during the day, because I was dealing with Apple and wanted to show the guy what I was seeing.

I could take another shot in the dark, but the original image highlights the problem just fine, unless people are really desperate to see it.

Hearing that all the iMacs have this gray bar issue to some extent is funny, because looking back at the shots from my first machine, (I'm on my 2nd), I actually did notice a gray bar in the same position, though the yellow was much more distracting.

I can live with it for the time being, but a replacement is coming my way anyways, so I guess I'll be on my 3rd machine.
It sucks because I can't go ahead and load all my stuff on here like I did with the first machine.

If the new MBP comes out soon with i7, and my 3rd machine is problematic, I may just go with a MBP + ACD combo instead, but like a lot of us out there, I want to give the iMac a chance. This 27" screen provides the type of resolution I have always wanted (I was using 1280x1024 max for years)

The thing I am glad I heard from Apple: "We will keep sending you a machine until you get one you like."
Which wasn't even something I had to draw out of them, its great that Apple is doing that, I just don't want the norm to become 'send back your machine 5 times until you get one that performs as it should.'

[Buzz Bumble]

Someone else reported what sounds like the same issue about two weeks ago in this MacRumors topic. Looks like "yellow tint" and "flicker" might be fixed, but now there's "gray banding", although so far it seems to be much rarer than previous issues.

[Pachang]

Originally Posted by Buzz Bumble

Someone else reported what sounds like the same issue about two weeks ago in this MacRumors topic. Looks like "yellow tint" and "flicker" might be fixed, but now there's "gray banding", although so far it seems to be much rarer than previous issues.

It's not NOW there's this problem that wasn't there before. They have had this problem from the start it's just that people didn't notice because their screens were yellow. It isn't much rarer. It is much more common just much less noticeable.

Every single 27" iMac I have seen has had this problem to some extent. Only one of them had yellowing.

I should mention that on one of them the dark band at the bottom was barely noticeable and not worth returning if you had it.

[lexvo]

I never noticed, but after setting the background to middle gray, I saw the gray band on my iMac too Not as bad as the screen of the OP though.

[xingstar]

Originally Posted by Pachang

It's not NOW there's this problem that wasn't there before. They have had this problem from the start it's just that people didn't notice because their screens were yellow. It isn't much rarer. It is much more common just much less noticeable.

Every single 27" iMac I have seen has had this problem to some extent. Only one of them had yellowing.

I should mention that on one of them the dark band at the bottom was barely noticeable and not worth returning if you had it.

Agree. I have seen this grey banding issue on almost every single 27 iMac I have seen so far. However 21 iMac seems ok from the local apple retail store I visited.

[Buzz Bumble]

Originally Posted by Pachang

It's not NOW there's this problem that wasn't there before.

Now the problem is being reported.

They have had this problem from the start it's just that people didn't notice because their screens were yellow. It isn't much rarer. It is much more common just much less noticeable.

Every single 27" iMac I have seen has had this problem to some extent. Only one of them had yellowing.

I should mention that on one of them the dark band at the bottom was barely noticeable and not worth returning if you had it.

Then maybe you should have reported it back then so that others knew and Apple might have fixed it by now.

[Kabir8]

Its easy to come out and say that all the iMacs have this issue, now that the issue is being talked about more frequently.

The fact that Apple finds this issue to be a "First" and that they are using my picture to show the rest of the engineers the problem that I guess has went unreported for a long time, shows that it is a defect, and not just part of what you get on the product.

What if the iPad came out and had a faint gray line in every single model manufactured? You think people would not notice, when reading text documents, ebooks, etc?

Maybe a tweak in manufacturing to prevent "yellow tinged screens" has in turn produced a higher frequency of "gray banded screens"?
Just a theory, but I have only had 2 machines so I can't make a definitive statement on that.

I am noticing that the severity of the gray band does vary, however it is far from discrete when I boot it up.

[MT0227]

I've seen this issue on every 27" imac I've come across; however the problem was more pronounced on some and fairly faint on others.

Approximately 12 floor modes between 4 different stores; 3 in NJ and the 5th avenue store in NYC. Most have been week 46-48.

I've also had 5 new boxes opened for me ranging from week 6 - 8, again all with the issue and again, more pronounced on some and fairly faint on others.


Here is my original post: http://forums.macrumors.com/showthread.php?t=867965

[wessew]

Kabir8, sorry for the delay in responding. My display is a 30" Apple Cinema Display calibrated with a Sypder 3 Express. As I mentioned, the screen looks better than many I have seen.