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annoying backlight bleeding on new panny

roxieman
12-06-2010, 11:06 AM
Just recently, (last week) bought a new panasonic TC-L42D2 LED edge lit panel. First I had some problems adjusting the the color to my satisfaction but after playing around with it for quite some time finally did get to what I consider a very good picture. However now what is annoying the heck out of me is backlight bleeding on the bottom of the screen. In any dark seen you can see 2 large inverted V's coming up from the bottom of the screen. Turning the backlight down will reduce the bleed through some what but there goes the picture quality. I have searched throughout the web and have not seen any thing in regards to this model with this problem. I am wondering if I just got a bad set? Another observation with this model is the extremely reflective glass on the screen. Panasonic typically uses a matte finish on their LCD'S but put a very shiny one on this panel. Much like a mirror. I am at this point tempted to make a return to Sears where I putrchased this set. This model at Sears if any one is interested is now currently selling for $679.00 which is $70.00 cheaper than what I paid 1 week ago. Either this set isn't moving well or was terribly over priced to begin with and has some inherent proiblems. Anyone have any experience with the Panny TC-L42U25 ? Am thinking this LCD might better suit me!

megantheweasel
12-06-2010, 11:47 AM
I can identify with your post. Took delivery of the L42D2 yesterday. After of about 4hrs of calibrating, I got the set to look very good with 1:1 pixel mapping connected to the PC running Windows 7 media center. The set has great colors, blacks, but the flashlight effect is a little bothersome. I wonder if this is a common flaw with Edgelit LED's in this price range.

d6500k
12-06-2010, 12:01 PM
A quick question.

Is the display on its base stand or hung from the wall?

Doug k

PFC5
12-06-2010, 12:26 PM
Viewing angles will effect all LCDs. Also edgelit LED lighting will have some backlight bleeding on most if not all brands. This is why full array LED backlit with local dimming is preferred, but very few models have this now because mfg want them thinner and for some reason people want thinner. I don't understand this since on a wall or stand what difference does 2" compared to 4" make especially when PQ is the price to pay for the thinnest sets.

megantheweasel
12-06-2010, 12:54 PM
Mine is setup on the stand, and I can see the bleeding more so when standing up looking down onto the TV vs in direct eye-level. So a full-array LED set will not have backlight bleed? Also, what is the advantage of a full-array LED over CCFL? Better blacks, less power consumption?

PFC5
12-06-2010, 12:58 PM
You will still have viewing angle issues with ANY LCD including the full array LED backlit with local dimming as well. It is a current limitation of the tech for LCD.

If viewing angles are an issue then you might want to consider a plasma since they have much better viewing angles, a uniform screen lighting (each pixel is it's own light source), and generally you can get better blacks & PQ with them for less money too.

roxieman
12-06-2010, 01:04 PM
In response to your question Doug it is on the stand and not the wall. Sorry to hear that you are also meagantheweasel having the same problem with the bleeding. I am starting to think that this is indeed a problem with edge lits or at least some of them. I rteally wonder if the old standard ccfl LCD might not have this problem. I do agree that once calibrated this set has incredible color and generally just a really nice picture. I am going to go and talk with the people at SEARS about this tommorow for what it is worth. I am considering an exchange for the U25 that I am guessing is the same IPS panel and everything else except for the Ipod dock and the edge lit LED's The price tag is about $250.00 cheaper "suggested" but is currently selling for a higher price. Do they know something we don't ?

megantheweasel
12-06-2010, 01:11 PM
PCF5: Thanks for the info. Because, the usage will be for computing and movies, I figured that an LCD/LED backlit set would be more suited for text. Is this a correct assumption to make or will 1080p plasma displays give you the same crisp text?

megantheweasel
12-06-2010, 01:22 PM
Roxie: Yes this is a real bummer as I don't know if I can live with this nusance. I have 3 other LCD, 2x24" and 1 27",that do not have this bleed. Maybe I should have gone with the Samsung LN40C630 for $600. Panasonic plasmas are well regarded but how are their LCD's?

PFC5
12-06-2010, 01:39 PM
In response to your question Doug it is on the stand and not the wall. Sorry to hear that you are also meagantheweasel having the same problem with the bleeding. I am starting to think that this is indeed a problem with edge lits or at least some of them. I rteally wonder if the old standard ccfl LCD might not have this problem. I do agree that once calibrated this set has incredible color and generally just a really nice picture. I am going to go and talk with the people at SEARS about this tommorow for what it is worth. I am considering an exchange for the U25 that I am guessing is the same IPS panel and everything else except for the Ipod dock and the edge lit LED's The price tag is about $250.00 cheaper "suggested" but is currently selling for a higher price. Do they know something we don't ?

All LCDs have some form of backlight bleeding. It comes because LCD crystals produce black by trying to block the light by twisting the crystals, but cannot completely block the light.

PFC5
12-06-2010, 01:44 PM
PCF5: Thanks for the info. Because, the usage will be for computing and movies, I figured that an LCD/LED backlit set would be more suited for text. Is this a correct assumption to make or will 1080p plasma displays give you the same crisp text?

Full screen movies are not a problem even when screaming, but using a plasma for more than 5% computer use is not adviceable because there is always static images in programs (i.e. ttitle bars, start menu, etc.) that could cause severe Imagine Retention and possibly burn in, but for other uses IR/burn-in is mostly a non-issue and not a problem as long as you do not have static images on the screen. IR can still happen but after the break in period is likely only going to be seen on a black screen if it shows at all and not with content. LCDs can get something similar called Crystal memory but it is harder to get.

If you need it as a computer monitor just stick with LCD and know it is part of the way it is, and the price you pay for using it as a computer monitor.

megantheweasel
12-06-2010, 02:27 PM
PFC5- Perhaps all LCDs have some amount of bleeding, however in this case it's noticeable and distracting from the viewing experience. Good point about plasmas regarding IR, but then too, am I right that they can't display text as sharp as LCDs.

PFC5
12-06-2010, 02:37 PM
You SHOULDN'T display text on your plasma IF it is more than 5% of the displays use. It could be plenty sharp enough since the same number of pixels are involved on comparable 1080p displays with each tech though.

After watching on my plasma all LCDs I have seen are ALSO distracting with back light bleed and noticeable to me. :D

dsskid
12-06-2010, 02:46 PM
Try a Sharp.

roxieman
12-06-2010, 09:52 PM
Hey Megan, just watched spiderman which has a lot of dark scenes and it really wasnt to bad. I suppose I can get used to it. Can't help but wonder if all of the panels in the this series have this problem though. Would like to compare mine to another because a small amount of bleed through is probably normal. I to looked at the Samsungs but i don't like the picture on their sets. Too unreal and fake looking. Thats why I went with the Panny to begin with. Softer more life like picture. Unfortunately I cannot comment on the rest of their LCD panels because I have only seen them in stores. I do know if you search for reviews on these sets they are generaly very good. May call Panasonic and ask about the bleed through and if I find anything out I will post it here. Still think Panasonic makes a great product so I am trying to keep the faith.

megantheweasel
12-06-2010, 10:16 PM
ROXIE: Glad to hear. I just got done watching Monsters vs. Aliens. Gotta say I was impressed. I cranked down the backlight to 40, and I agree, it's not that noticeable unless you're looking for it. The blacks are great. I know what you're saying, the Samsung panels are very sharp, almost too digital looking? This TV works great as a computer monitor, and barely gets warm. Though I'm not too crazy about Panasonic's thick bezel design, I've decided to just keep it as I've read the bleed is common a drawback on most edge-lits. Glad I don't have deal with the guilt of returning the TV.

neoshredder27
12-06-2010, 11:34 PM
Gotta love buyers remorse. lol

kharaa
12-07-2010, 12:29 AM
LCD's generally have a sharper crisper image with more pop, where plasma usually has deep blacks and accurate colors, giving a very accurate picture

This is also one of the reasons I think LCD's are better for computers, I don't notice any bleeding on my Toshiba LED-LCD, but maybe i don't know what i'm looking for, or i'm just not sensitive to it.

d6500k
12-07-2010, 11:00 AM
Mine is setup on the stand, and I can see the bleeding more so when standing up looking down onto the TV vs in direct eye-level.

PFC5 mentioned the off axis situ's and your "looking down" Vs. direct viewing verifies the anomaly.

My reason for the "on the wall" question is that I have seen displays that are tilted down sharply, thus "hanging" from the back of the display, can cause a bit of warping on the set itself. When this occurs, it is not unlike pressing ones fingers to a lcd monitor squeezing if you will, the corners to cause some light bleed due to the compression of the lcd matrix. 'tis the nature of the beast.

Doug k

neoshredder27
12-07-2010, 11:40 AM
LCD's generally have a sharper crisper image with more pop, where plasma usually has deep blacks and accurate colors, giving a very accurate picture

This is also one of the reasons I think LCD's are better for computers, I don't notice any bleeding on my Toshiba LED-LCD, but maybe i don't know what i'm looking for, or i'm just not sensitive to it.
Yes this is pretty accurate. Not sure about crisper but it is definitely brighter. Plasma's give you rich colors though. Very good with nature programs and programs with a lot of color. More natural looking. Plenty clear though.

dsskid
12-07-2010, 01:17 PM
Blanket statements that plasmas have better color accuracy than LCDs is false.

There are many LCDs that have excellent color accuracy, and some plasmas have poor color accuracy. Lower end models of both technologies tend to suffer, and mid and upper level models fair better.

I crack up everytime someone makes the "LCDs are too bright" comment.

They are only too bright if you leave don't take the time to properly adjust backlight and contrast levels from their default values. The are very capable of being dim.

neoshredder27
12-07-2010, 02:30 PM
Blanket statements that plasmas have better color accuracy than LCDs is false.

There are many LCDs that have excellent color accuracy, and some plasmas have poor color accuracy. Lower end models of both technologies tend to suffer, and mid and upper level models fair better.

I crack up everytime someone makes the "LCDs are too bright" comment.

They are only too bright if you leave don't take the time to properly adjust backlight and contrast levels from their default values. The are very capable of being dim.
Yes and the pop goes away from LCD's once you take away the brightness. Than the factors of black levels come in play. Plasma's give you a much smoother and softer picture in a dim room. The colors are more rich. They seem more natural to me. Plasma's can get bright and LCD's can get dim but neither look as good when going to the extremes from the main settings. I was thinking more of the artificial sharpness that LCD's add to their picture offer can be annoying over time and give you a headache. I'm sure the color is fine but not as impressive imo. I was comparing tv's of the same price range.

dsskid
12-07-2010, 06:25 PM
Not saying LCD is better than plasma. Just dispelling some myths.

roxieman
12-07-2010, 10:34 PM
Thats what I love about this forum. You can start out with a question about backlight bleeding and the next thing you know your talking about what type of panel we should take to the moon. If your on the dark side I would say Plasma, the bright side well, you know. Hey weasel I though you should know (if you see this) I talked to numerous people about the bleeding and it was the first they have heard of it with this series. Go figure

neoshredder27
12-07-2010, 11:10 PM
Thats what I love about this forum. You can start out with a question about backlight bleeding and the next thing you know your talking about what type of panel we should take to the moon. If your on the dark side I would say Plasma, the bright side well, you know. Hey weasel I though you should know (if you see this) I talked to numerous people about the bleeding and it was the first they have heard of it with this series. Go figure
You also gotta put in the weather changes. Plasma's have trouble in high altitude. Tough weather conditions on the moon will probably be not suitable for Plasma. :D

megantheweasel
12-08-2010, 12:57 PM
Roxie: Do you think the people you inquired notice the flashlight effect even if it was there? I assume that there are many who just plug and play their TV using factory settings, would probably never notice a flaw such as this.

I turned down the backlight to 35, and adjusted the brightness and contrast to my liking. Played Beowolf with plenty of dark scenes, and hardly noticed the flashlight effect with the lights turned off in the room. However if I'm searching for it or if not viewing at eye level at certain angles the bleeding is visible. Got to admit the TV would be perfect without this issue and when used as a monitor there are no complaints.

I also have 3yr old LG 42" 720P plasma that holds up quite well for watching movies, but then there's the Bzzzzzzzzzzzzzz, heat, and it doesnt come close to the sharpness of any of my LCD's. IMO, plasmas for movies because it has better motion flow, blacks, and..... :yippee: no backlight bleeding issues..

PFC5
12-08-2010, 02:59 PM
Roxie: Do you think the people you inquired notice the flashlight effect even if it was there? I assume that there are many who just plug and play their TV using factory settings, would probably never notice a flaw such as this.

I turned down the backlight to 35, and adjusted the brightness and contrast to my liking. Played Beowolf with plenty of dark scenes, and hardly noticed the flashlight effect with the lights turned off in the room. However if I'm searching for it or if not viewing at eye level at certain angles the bleeding is visible. Got to admit the TV would be perfect without this issue and when used as a monitor there are no complaints.

I also have 3yr old LG 42" 720P plasma that holds up quite well for watching movies, but then there's the Bzzzzzzzzzzzzzz, heat, and it doesnt come close to the sharpness of any of my LCD's. IMO, plasmas for movies because it has better motion flow, blacks, and..... :yippee: no backlight bleeding issues..

You should see the newer 1080p plasmas for a proper comparison as they have improved just like the LCDs have improved. They can look just as clear with the 1080p plasmas as with LCDs for text, etc, since they are the same resolution. They newer plasmas have also improved a lot with black levels since your 720p model came out 3 years ago too. ;)