IPS Panasonic HDTV: Is this backlight bleeding acceptable?

applebook

Limp Gawd
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I just picked up this 32-inch CCFL 1080p IPS Panasonic last night and am disappointed with the lack of uniformity of the backlight. The sides, especially the bottom left, appear significantly brighter than the middle when there is no image (backlight set very high at 75%). However, when I'm watching most full-screen stuff, the bleeding is not very noticeable. Still, I find this very bothersome because it's worse than my 3.5-year-old PVA Aquos. Do you think it is worth exchanging? I HATE to depend on others for rides, so I'd rather not bring it back if possible. I am not springing an extra $450 (after taxes) for the LED 120Hz Panasonic. That's too much money right now. Plus, the LED version will have its own set of problems, and I do not use dynamic contrast anyway.

Backlight.JPG


Backlight2.JPG
 

LTomes

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If I were using it for movies it would be acceptable. But if you use it with my computer (any reading) it would drive me insane and I would return it. If you bought it at a store where there is a display compare yours to theirs. Thats all the advice I have! Good luck!
 

Godmachine

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For my tastes no .. without question. I would return it. I'm very picky about back light bleed though.
 

applebook

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I should say that the bottom picture is not at all indicative of how the backlight looks in real life. The top is more representative. Like I said, during actual usage, I would have to squint pretty hard to notice that the bottom left is slightly brighter than the rest of the display, but it does bother me.

I bought it at BB, so exchanging it is no problem --I would just need to get a ride.

The problem with testing the store models is that under normal lighting conditions, the backlight looks almost perfectly even. If I can get a ride, then I guess I should exchange it.
 

SJetski71

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Not acceptable imho OP.

I have a 32" 2009 Panasonic IPS, and at 80% backlight it would have a light tinge in the extreme lower left corner only.

Lowering the backlight down to 65% virtually eliminates it though, and makes everything nice and even.

It's worth the trip imho, pack it up in the car and exchange it, chances are your next set will be better.
 

nobody_here

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only if you are watching nothing

turn on a source, put something in and enjoy it...shessh
 

macrospect

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The second almost looks like IPS glow which would be normal but judging from the first one, that is pretty bad if it really looks like that in real life and would return the panel.
 

kkt

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OP, if it really bothers you then I would say go ahead and exchange for another one. However, please keep in mind that there is no guarantee that the next one won't have the same screen non-uniformity. Worse yet, it could be plagued by dead pixels, which imho, is worse than (minor) screen bleeding. You wrote in the post that the pictures were taken at a "very high" 75% backlight--is this the setting that you would normally use? Have you tried calibrating the set yet? Unless the bleeding is really severe, proper calibration can help to reduce the un-eveness in the screen and give the LCD a more life-like image. Keep us in on what you plan to do.
 

tk-don

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What model is this? The glow doesn't look like anything i'd seen from IPS Alpha, so mainly curious to know if it's an LG or IPS Alpha panel
 

SJetski71

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What model is this? The glow doesn't look like anything i'd seen from IPS Alpha, so mainly curious to know if it's an LG or IPS Alpha panel
He has a 32" 1080P panasonic, which makes it an IPS-Alpha. It's only the larger sizes when Panasonic would occasionally use LG's S-IPS.

The bottom picture he posted was taken from a higher vertical angle, which explains why it looks washed out like that. And because of that it isn't a good picture to diagnose that TV's symptoms, the OP should delete that picture imho.

Not to mention that camera photos always make backlight bleed look worse than it really is.

only if you are watching nothing

turn on a source, put something in and enjoy it...shessh
Not true, that backlight bleed is ruining that panel's black levels, which are somewhat poor to begin with. You may not mind, but the OP was obviously expecting something better ;).
 
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applebook

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Here is the model: http://www.bestbuy.ca/en-CA/product...spx?path=9402a8e09e344552ff1f29de53fb42f1en02

It's only $450 CDN in store, but there is no TW polarizer, thus the typical IPS white glow when viewed from angles.

I have calibrated the display and actually do run the backlight at 70% (brightness really low though), and like I wrote earlier, during normal usage, the unevenness is not as noticeable as the "test," but if I have a dark picture on the bottom left, I do perceive that it's 10% brighter than the rest of the screen. I could lower the backlight setting and turn up brightness, but doing so reduces image and photo sharpness and color vibrancy too much.

I don't expect the backlight to be perfect, but being nearly 4 years newer and having an IPS panel, the Panasonic should be better than my last set.

I am going to exchange it and just hope for the best.
 

tk-don

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He has a 32" 1080P panasonic, which makes it an IPS-Alpha. It's only the larger sizes when Panasonic would occasionally use LG's S-IPS.
Forgot it probably was a US/Canadian model... at least in Europe, certain series exclusively use 1080 panels from LG (also in 32", and especially in 26", since IPS-Alpha don't seem to want to produce these any longer). They are of course also priced lower than the sets using their own panels. But if that's an IPS Alpha panel, it's definitely sorted to reflect the price somwhat - it does not have the extra polarizer to prevent white glow in vertical angles and apparently they let a panel with that kind of uniformity leave the factory.
I'm not saying they're all equally bad - just that the "variance" may be high.
Btw. the best panels with the right polarizers applied closely resembles A-TW IPS panels.

Applebook, I agree - i think you should try exchanging it. Are you able to compare different Panasonic TVs instore closely enough to notice if they all have the same viewing angles on "dark material"?
 

llmercll

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It does look like glow, because of the "dynamic" appearance when changing angles.

But I really have no idea =p
 

applebook

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Applebook, I agree - i think you should try exchanging it. Are you able to compare different Panasonic TVs instore closely enough to notice if they all have the same viewing angles on "dark material"?

Not possible because the lighting too bright at Best Buy to have a good look-see.

Well, I played TF2 tonight, and with my rig, I probably get over 100fps, and guess what? There is noticeable ghosting that was never a problem with my old Aquos!

I'm likely going for the 32-inch LED, 60Hz Samsung at $599 CDN. Do you folks think these numbers are accurate? TheTVreview.com states that static contrast for each panel is
- 37" version Panasonic: 2900:1 http://thetvreview.com/panasonic-tc-l37u22-37-inch-1080p-lcd-hdtv-review/
- Samsung: 2500: 1 http://thetvreview.com/samsung-un32c5000-32-inch-1080p-60-hz-led-hdtv-review/

The difference isn't big, but it is interesting to note that the CCFL IPS Panasonic has noticeably higher contrast.

One other question, do Samsung PVA panels still have that annoying bright left side problem? My Aqous was clearly brighter on the left than towards the middle and the right.

Unfortunately, because of my room, I don't have space for a 40-inch plus display, or else I would probably go for a 120Hz CCFL LG with an IPS panel. There aren't many options in the 32-inch 1080p class.

Panasonic3.JPG

Panasonic4.JPG

Panasonic5.JPG



UPDATE: I turned off Vsync on T2F and all digital filters on the TV, and input lag is now virtually imperceptible in both New Vegas and TF2. The measured delay is between 31-47ms, which while not fast, is by no means terrible or unplayable.
 
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nobody_here

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He has a 32" 1080P panasonic, which makes it an IPS-Alpha. It's only the larger sizes when Panasonic would occasionally use LG's S-IPS.

The bottom picture he posted was taken from a higher vertical angle, which explains why it looks washed out like that. And because of that it isn't a good picture to diagnose that TV's symptoms, the OP should delete that picture imho.

Not to mention that camera photos always make backlight bleed look worse than it really is.

Not true, that backlight bleed is ruining that panel's black levels, which are somewhat poor to begin with. You may not mind, but the OP was obviously expecting something better ;).

Sure...but the black levels are not what they are when viewing an input as they are when viewing nothing. What the heck happened to buying a nice tv and enjoying it? Cant see the forest for the trees comes to mind.
 

applebook

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The backlight test indicates how deep the darkest blacks can be at a particular backlight level setting. I've never seen enormous backlight bleeding that resulted in perfectly fine and uniform blacks during normal usage.
 

SJetski71

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Sure...but the black levels are not what they are when viewing an input as they are when viewing nothing. What the heck happened to buying a nice tv and enjoying it? Cant see the forest for the trees comes to mind.
Backlight bleed spills thru even when there's dark content on the screen.

I'm not sure if it spills thru less when there's actual content but my eyes do not lie.

Don't get me wrong otherwise, i fully hear what you're saying, and even agree with some of the other stuff. But if the OP was unsatisfied and willing to exchange it, there's no reason not to, he'll either end up with a better TV, or a worse one :p
 

seanmcd

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Don't obsess over this OP. Just about every lcd panel I've owned has looked that way but worked fine.
 

applebook

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Well, I exchanged the Panasonic for an S-IPS 1080p 37" LG (37LD450) at the same price on sale. There is a massive panel lottery with the LG: some of these LGs are TN, MVA, IPS-Alpha, and S-IPS (which is what I ended up with).

Input lag is measured at an excellent 16-32ms, and ghosting/motion blur, while not amazing, is imperceptible to my eyes when playing TF2.

Basically, for anyone looking at a CCFL LCD, I wholeheartedly recommend the LD450 series over the Panasonic U22 because of the faster pixel response, lower input lag, and S-IPS panel. The Panasonic does have slightly deeper blacks and overall contrast but only if you crank up sharpness and backlight settings, which ruin text and introduce glaring artifacts. The LG's S-IPS has significantly less white glow when viewed at an angle. I'm quite surprised that despite being much larger, the LG's backlight is far more even, and viewing angles are wider too. Another bonus is that the LG includes a plethora of image/color adjustments that are missing on the Panasonic.

Colors are more realistic right out of the box on the LG. Despite my best calibration efforts on the Panasonic, reds and particularly blues are overly saturated and BLEED considerably. Without the ability to change the RGB values individually on the Panasonic, one cannot get accurate blues and reds from it without sacrificing overall color vibrancy. Oh, and the LG has a swivel stand too, although the Panasonic's mounting brackets are steel as opposed to the rather flimsy plastic of the LG.

One final note is that I could not turn dynamic contrast completely off on the Panasonic, whereas the LG easily allows me to do so. The dynamic contrast on my old Aquos always irritated me when I was surfing the web.

LG.JPG

LG3.JPG

LG5.JPG

Can you perceive any unevenness?

P.S. I don't like Ferrari, and Fernando Alonso is scum. That model car was a gift.
 
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SJetski71

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Wow, good move applebook. Thanks for the follow-up and comparison. Now all you have to do is sit back and enjoy it.

Or if you are like the rest of us, you can hunt down tweaks to squeeze the last 1% of image quality out of it. At the very least make sure your fonts are 100% crisp. That model LG is once of the current favorites for monitor use, you chose well imho.

And as a sidenote, the U22 series was not Panasonic's best implementation of their IPS-alpha panels. Their 2008 and 2009 models seemed to be better with less input lag, more menu tweaking options, and less blue push (you only had red to deal with).
 

applebook

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I don't like the various calibration profiles posted on AVS for this LCD. They may be quite accurate, but I find images and colors dull and lacking contrast. My backlight settings are 55 to 65, depending on content, brightness 40-50, contrast 95, and V-sharpness 55, H-sharpness 65. I haven't done much with the very numerous color settings yet.
 

Godmachine

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I don't like the various calibration profiles posted on AVS for this LCD. They may be quite accurate, but I find images and colors dull and lacking contrast. My backlight settings are 55 to 65, depending on content, brightness 40-50, contrast 95, and V-sharpness 55, H-sharpness 65. I haven't done much with the very numerous color settings yet.

I find that many user posted color profiles are just not to my liking for any display I've used. Everyone has different eyes and different levels of contrast and color they can observe.

Professional calibration can be nice but unless you need dead standard values for the most neutral picture possible which is good for Blu-Rays and TV (allowing the content to be displayed as the director intended) or you need a computer monitor calibrated for some kind of professional photo editing or you review displays for a living then adjusting the levels to your own liking by using even a basic test pattern is more than acceptable.

There is no rule requiring you to spend countless hours adjusting your picture , just set it how you like it and enjoy.
 

SJetski71

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Ya i was mostly referring to tweaking settings to make the display more suitable for monitor use, stuff like sharpness, overscan, dot for dot, disabling many of the "picture enhancements" in the TV menu, cleartype etc etc.

Seems like you're on it though.
 
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