Greyish Smudge marks behind the glass screen.

Can we set up a poll or something to figure out if there's a pattern to all our woes? For those that have severe screen "dirt" and are not smoking near the computer nor have hygiene of pig pen:

1) Do you have an ultrasonic humidifier?

2) Is your iMac in a desk enclosure that may be limiting ventiallation on top?

Let's see if we can figure out the culprit. For me, it seems to be #1. I have an ultrasonic humidifier, in the other end of a large room, and if I turn it high and leave it on overnight, in the morning, the "dirt" factor is visually worse. For #2, I have about 2 inches on top and plenty clear in the back, so I don't think that is it.

The POLL is useless, Its a design fault simple as that

You could live in a house WITHOUT a humidifier ** and LOADS of desktop space for the Imac.

Seems you just have a bad one, Same as everyone else on here.

Some front screens have the weird frosting / blemishes in the corners that can be cleaned by simply taking of

front screen ( I had this as well and resolved it easily ) and cleaning.

99% of the issues in this thread are due the design fault.

If these machines ever get recalled and you have done THE FIX yourself ( ie. taken LCD apart ),

I'd wager your warranty will certainly be invalidated so I'm holding fire for a few months to see what happens

as more and more people are getting onboard with the same issue.

cheers

rob.

** Like this should make a diff on a £1700 machine. ( my old imac is in the same room and

has been for 3 +yrs ), Screen issues on this...Nope!.

I'm actually concerned that my iMac may eventually blow up or simply not start one day.

I'm concerned about that as well, but on the bright side, maybe then Apple will recall them.

Well yeah that's a good point lol.

Grace,

The Smudges DO NOT AFFECT THE WORKING OF THE MACHINE.

It will toodle alone fine for years. It will just get smudgier and smudgier and yellow/brown hazier over time

It's an irritation but will NOT affect the normal working of the machine.

NOW that being said, Most of us think that the working of the machine includes a beautiful display because that is one of the reasons we bought it. So when you're working on a picture and the color of the screen in inconsistant then as far as we're concerned it affects the working of the machine because it affects our work.

I can't choose colors correctly if my screen is not consistent...

But no your machine will not stop working because the screen is a bit hazy.

...or unless it exploads.

Thanks for that. I hope to get another two or more years out of it as it's a replacement machine and my second one at that I wouldn't like to think I'd have to spend more money in a hurry. I don't use it for any graphic work but it is an ongoing pain and we shouldn't have to put up with it but because Apple constantly blames us and our enviroments there isn't much we can do.

I have the same problem on a 21.5" late 2009 Imac, I have had the LCD replaced three times, I dont even have it in the same room as the humidifier. they are honoring the applecare, but at the same time, since I have to bring it in every 6 months or so, Im out of a computer for a week. The last time I had it replaced, the spots returned within a week.

I've given up to be honest.

Like a lot of people here, I have the same problem on my 27" mid 2011 Imac...

Screen replaced thanks to applecare, but about one month later, the spots returned like wanderingjew...

It's very disappointing for such an expensive computer. It's my first experience with Apple and maybe my last too...

I don't understand why Apple doesn't recognize the problem and fix it for good.

There's nothing more irritating than having such issues with a computer at that price and hearing the applecare support speaking about an environmental problem. As if they were not aware of the problem...

And I begin to seriously regret my choice for this computer, my choice for Apple...

Is this the way Apple chose ? : low cost and bad quality computers sold at exorbitant price ?

I don't think it will last long this way.

So, Apple, please, do something to fix the problem definitely. And tell to your support to stop considering us like idiots because enough is enough.

This may be a design flaw, but it's not the LCD, it's just dust gather behind the glass panel. The glass panel is easily removed with suction cups (it's magnetic). You just put a suction cup on the top part of the screen and pull outward, and the whole glass panel comes off. Then you can clean the inside of the glass panel, and the inner LCD with a microfiber cloth. Apple then uses a silicon roller to clean out all the dust the cloth left behind(you can buy them online) and you can put the glass panel back on. It's a 10 minute job total to do the cleaning.

I appreciate that you're trying to be helpful, but what you're posting is simply not correct (for what we're experiencing).

Is this something that can be solved by removing the glass panel? (pics halfway down page)

http://forums.macrumors.com/showthread.php?t=1101370&page=2

Or this?

http://www.hardmac.com/news/2011/04/05/investigation-of-the-marks-on-the-imac-sc reen

Or would Apple have replaced some screens *multiple times* for people in this thread experiencing this issue? If it were just a matter of removing the glass screen and using a microfiber cloth?

Again, apologies for sounding like a jerk in my response but it's incredibly frustrating when people come in and presume that this is some kind of "simple fix" and not a serious design issue that is plaguing some of our screens with no easy solution than to beg Apple to continue giving us replacement LCD's.

I agree this is a design flaw. I'm going to be on my second display soon. I'm also going to get rid of my ultrasonic humidifier. I just dont' understand why this doesn't effect EVERYONE. Clearly it effects a lot of us. But we all have dust in our homes. So what is the reason it's not happening to everyone? Do iMacs have different chassis types from certain mfg plants or something?

YOU ARE WRONG

It is NOT dust behind the glass panel!!!!!

I have done this now 4 times.

It is INSIDE THE DISPLAY between the layers of diffusers and the actual LCD!