<div class="quote-container" data-huddler-embed="/t/1554978/backlight-bleed-vs-time#post_23893758" data-huddler-embed-placeholder="false"><span>Quote:</span>

<div class="quote-block">Originally Posted by <strong>I--S</strong> <a href="/t/1554978/backlight-bleed-vs-time#post_23893758"><img alt="View Post" class="inlineimg" src="/img/forum/go_quote.gif"></a><br><br>

So, it seems a current topic... backlight bleed. Many, many complaints here about backlight bleed.<br><br>

A few months ago I bought my partner a Benq GW2765ht. Once set up it was fine, although I wasn't very happy with the backlight bleed on it. In all other respects it was fine (no dead pixels, no other issues). I did a little searching on the web and found a suggestion that might fix it, which I tried and it seemed to improve it. After a while (a few weeks) looking at the monitor (which I wasn't using regularly, just glances) it seemed to me that it was actually fine. Had I just got used to it?<br><br>

I loaded up a black screen on ms paint, full screen to purposely go and look for the bleed.<br><a class="spoiler-link H-spoiler-toggle" href="#"><strong>Warning: Spoiler!</strong> <span class="spoiler-help">(Click to show)</span></a><div class="spoiler-hidden"><a class="H-lightbox-open" href="http://www.overclock.net/content/type/61/id/2450324/"><img alt="" class="lightbox-enabled" data-id="2450324" data-type="61" src="http://www.overclock.net/content/type/61/id/2450324/flags/LL" style="; width: 1001px; height: 667px"></a><br><br>

1/4th, F4, ISO 1600<br><br>

Really nothing significant - the top right and bottom left are IPS glow - only the bottom right of the screen exhibits a slight backlight bleed, but now one that you have to go purposely looking for (whereas when it first arrived it was obvious).<br><br>

On the 30th April I received my new Acer XB270HU. I got it set up, calibrated, etc and like quite a few people here I was disappointed with the backlight bleed that I was experiencing. I loved the smooth motion of the monitor (coming from a regular IPS display, overclocked to 75Hz), and the size and everything else, but the backlight bleed seemed.... overwhelming.<br><br>

I repeated the trick that I had applied to the Benq and again seemed to get some improvement. After a few days (I wasn't sure on the thursday about its performance and wanted to evaluate it over the 3 day weekend) I felt that it had improved further, and at that point I took this picture (4th may):<br><br><a class="H-lightbox-open" href="http://www.overclock.net/content/type/61/id/2450325/"><img alt="" class="lightbox-enabled" data-id="2450325" data-type="61" src="http://www.overclock.net/content/type/61/id/2450325/flags/LL" style="; width: 1001px; height: 667px"></a><br><br>

1/4th, F4, ISO 1600<br><br>

Bleed spot on the bottom edge toward the left of the screen, and a larger bleed area above the OSD buttons at the bottom edge on the right. Again, the areas at the top of the screen are IPS glow.<br><br>

At this point I found that the real-world performance of the monitor was perfectly acceptable, so since then I left it alone.<br><br>

Today (11th may) I decided to see what the impact of another week has been, if any. I loaded up the black screen again...<br><br><a class="H-lightbox-open" href="http://www.overclock.net/content/type/61/id/2450326/"><img alt="" class="lightbox-enabled" data-id="2450326" data-type="61" src="http://www.overclock.net/content/type/61/id/2450326/flags/LL" style="; width: 1000px; height: 667px"></a><br><br>

1/4th, F4, ISO 1600<br><br>

Subjectively, and corroborated by the photo, the bleed patch at the bottom left side is now absent, and the bleed area at the bottom right is slightly reduced.<br><br>

So what's going on?</div>

My THEORY is this:<br><br>

Backlight bleed occurs when there is a misalignment in the backlight and panel substrate layers of the screen. This misalignment doesn't need to be big - just watch the effect on backlight bleed of getting a microfibre cloth and applying light finger pressure to the screen.<br><br>

When these panels first arrive at our homes and offices, they've pretty much been through hell - the panel has been fitted into a monitor casing, by screws or snap-fits, it has bits of casework and buttons pressing on it from every which way. Then it gets airfreighted in the freezing cold hold of an aircraft, then put in a truck, a warehouse subject to temperature variations, then your courier of choice gets to play drop football with it.<br><br>

When you're talking about very thin sheets of glass and plastic pressed together, this is not a good thing. Ultimately, all of this causes stresses and the resultant misalignments in the panel. This can result in backlight bleed.<br><br>

The solution can be as simple as letting the monitor settle down in the fairly stable temperature and humidity of your environment, to say nothing of no longer being thrown off the mail truck.<br><br>

The trick that I applied to both our monitors was simply to take a microfibre cloth and apply light pressure, running along each edge of the panel, pushing it slightly away from the front casing of the monitor, concentrating a bit more in areas where bleed is exhibited. By mechanically moving the panel relative to the casing you give it the chance and impetus to shift fractionally into its natural position. In effect it may merely accelerate the process which time will provide anyway.<br><br>

There are some issues, of course.<br><br>

The first is that when you get a new monitor you want it to be perfect out of the box - my theory is that this will rarely happen due to the factors listed above. The second is that when it's not, and an RMA might be in the offing then everyone wants to get the RMA done as quickly as possible. In other words, snap decisions about backlight bleed performance are being taken within minutes of the monitor arriving, so it never gets the opportunity to settle to the potential level it could.<br><br>

It would be really, really useful if someone who is getting a new monitor soon could help in the following way: Take a periodic set of images at a set manual exposure value, perhaps once a day from the arrival of the monitor, and if you choose to apply the panel "massage" trick then you could also do before/after of that.</div>

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Interesting observations ... hopefully other XB270HU owners will take note ... +R for the effort <img alt="thumb.gif" class="bbcode_smiley" src="http://files.overclock.net/images/smilies/thumb.gif">