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Discussion Starter · #1 ·
Could someone please put to rest the question of burn-in on lcd rear-projection tv's?


I was looking into getting the Panny PT50LC13, but watch a lotta 4:3 tv... will this be a problem for me? Please, someone help! :)
 

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Nope. No burn in.


Burn in, as you know it from CRT's, happens because of the phospors on the screen. The LCD rear projection screens have no phospors to burn, so it will not happen. It's just the LCD panel and a bulb.


(On a related note, the Samsung DLPs actually advertise "No Burn In". The analogy of these technologies as it relates to this question is, of course, tenuous, but they do share some obvious similarities.)


On another related note, I tend to watch my SD 4:3 TV on the Panny's "Just" aspect ratio (weird name, eh?). It's a nonlinear scaling that does a respectable job of fitting the 4:3 pic to the 16:9 screen without making people look too fat. And, of course, most HD programming will already be in widescreen. So this may never be an issue for many people even if they get CRT projections.
 

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No burn-in on LCD type displays. Don't worry be happy. :) Same with DLP.


Plasma and CRT Rear Projection/Front Projection are the main culprits when it comes to burn in.
 

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I used to post exactly what Cobalt said. It was truth as far as I knew it. Then when I got my Hitachi LCD, I was intrigued by the gray bars instead of black bars on 4:3. The set allowed us to change the gray bars to black but when you powered off the set the riverted back to gray. Hmmmmmmmm. Had to ask a tech rep from Hitachi about this and the reason was due to something he termed as "pattern burn". It seems that LCD does have a potential for a burn-in type issue. It is different and not as likely as say a Rear Pro CRT but it is a issue none the less. Bottom line: Limit your use of 4;3 and static images. Solution: learn to use stretch modes when possible. I know they suck but learn to use them and live with them and this issue is moot. It's a problem I am aware of as a LCD owner but not one I worry about.
 

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No, the debate is not in limbo.


Not at all.


There is no burn in.


None.


Zero.


Zilch.


Zippo.


Nada.


I don't want to claim I know what the Hitachi is doing or what anyone was speaking about. But here's what I do know: You cannot burn in an LCD using any conventional means (i.e. watching television).


In fact, I use my LCD projector -- the same kind of innards as in an LCD RPTV -- excessively in 4:3 mode. I watch that way 80% of the time. I have done this for around ~700 hours now. There is -- of course -- not the remotest hint of burn in. Why?


Because the technology cannot be burned in using this kind of behavior. The individual pixels have no clue they've been used differently. They all see light coming at them from behind constantly. And they either block it or don't. There is nothing about this that is akin to the way a CRT or plasma phosphor generates the illumination and makes burn in possible (although sill unlikely!).


Mark
 

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There is a chance that LCD can have thermal effects from 4:3. This has been seen in some LCD projectors. The effect has been reversible, but is a function of how bright the bulbs are and how effective the projector rejects heat. It shows up as a discoloration where the bars are. I don't know if the Panny gets hot enough with a 100 watt bulb for this to be a problem. The rear projectors that have this problem have bulbs that are about twice as bright (hot).
 

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I've read in other posts that LCD rear proj's are not subject to burn-in but, unlike DLP's, their pictures will fade over time. If this is true, would watching in 4:3 with black side bars cause an uneven pattern of fading and be a reason for the default to grey side bars and the suggestion to limit 4:3 viewing?
 

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Burn in no. By definition uneven phosphorus burn is not possible with LCD.


Image retention, maybe??? This has been talked about in the past and it seems to disappear after watching content that fills the screen for a while.
 

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Quote:
Originally posted by GLH
I've read in other posts that LCD rear proj's are not subject to burn-in but, unlike DLP's, their pictures will fade over time. If this is true, would watching in 4:3 with black side bars cause an uneven pattern of fading and be a reason for the default to grey side bars and the suggestion to limit 4:3 viewing?
The key is how long does it take the LCD to fade if there is such thing at all. Probably long before the mirrors inside DLP stuck or color wheel motors of the DLP set seize up. There is no double everything will fail over time. Do you really want to keep watching your TV for 20 or 30 years?
 

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In regards to what Hitachi told me, there was never a mention of Phosphoros Burn that is a problem with Rear Pro CRT's. The guy alluded to Pattern Burn which I took to be something different altogether. What UMR says sounds like a possible explanation to this phenomena.


There has been alot of prior discussion about the RP LCD manuals discussing the limiting of viewing 4:3 material and this has been largely dismissed here at this forum as the manufacturers copying from old manuals that applied to RP CRT's. Then I get the Hitachi set and the Black Bars are Gray and they allow you to set them to Black but then when you power off they revert back to Gray. Why did their engineers do this? Did they think that it looks nice or asthetically appealing? Because if they did then they are dead wrong because none of the Hitachi LCD owners are particularly pleased with the look. Or do they as engineers know maybe something that is a potential for a problem and have decided to lessen the risk? You be the judge.
 

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Quote:
Originally posted by Barrybud
Burn in no. By definition uneven phosphorus burn is not possible with LCD.


Image retention, maybe??? This has been talked about in the past and it seems to disappear after watching content that fills the screen for a while.
I've read about the image retention thing and was concerned for about 5 minutes with my LC13 after leaving the xbox for about 5 hours but after I changed to regular programming there was nothing there.

Maybe it would happen after longer use or over a longer period of time but nothing so far.
 

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Manpig,


I think the Hitachi engineer is just too lazy and copy and pasted the firmware from RP CRT set :D. If I remembered correctly, Sammy DLP manual also mentioned about burn in.
 

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Quote:
Originally posted by Foxbat121
Manpig,


I think the Hitachi engineer is just too lazy and copy and pasted the firmware from RP CRT set :D. If I remembered correctly, Sammy DLP manual also mentioned about burn in.
Fox,


Yeah, and the engineer that designed the tv thought the gray bars would look pretty.....kinda reminded him of his grandma Hirohito.
 

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100 hours! That's it? Guess I can't play my Xbox all week long... At this length, who cares?
 

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Quote:
Originally posted by manpig
In regards to what Hitachi told me, there was never a mention of Phosphoros Burn that is a problem with Rear Pro CRT's. The guy alluded to Pattern Burn which I took to be something different altogether. What UMR says sounds like a possible explanation to this phenomena.
I think we're talking about entirely different kinds of "burn-in" here. For plasma and CRT, it's the phosphor that gets aged with repeated bombardment from electrons (probably from the heat generated too). Since there's no phosphor for LCD projection TV's, obviously that's not the problem. My theory (similar to umr's) is that the "pattern burn" in LCD projection TV's results mainly from heat built-up on the LCD panels. Bear in mind that the projection lamp is very very hot in a LCD projection TV, and the LCD panels are rather close to the lamp. Evidence to support this theory is that black color (which absorbs most heat) seems to cause more pattern burn than light colors (which is why they use grey bars and not black bars in the Hitachi), which is the opposite of other types of burn-in where bright colors usually cause more burn-in than dark colors.
 

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Whatever LCD wear might occur -- as referenced above -- is due to the polarizers. So, no, that's also not an issue.
 

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Quote:
Originally posted by rogo
Whatever LCD wear might occur -- as referenced above -- is due to the polarizers. So, no, that's also not an issue.
Sorry I must have missed the reference to polarizers, where is it? If it's referring to the built-in polarizer in front of the LCD pixels, then it may be one and the same problem: excessive heat built-up may harm the polarizer, thus causing pattern burn.
 

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Quote:
Originally posted by rogo
There is no burn in.

In fact, I use my LCD projector -- the same kind of innards as in an LCD RPTV -- excessively in 4:3 mode. I watch that way 80% of the time. I have done this for around ~700 hours now. There is -- of course -- not the remotest hint of burn in.
Just to add: I have used my GWII LCD for about the same number of hours, almost exclusively in 4:3, and don't see anything in 16:9, either, and I have keen eye sight. Also, the instructions make no mention of needing to use full screen at all.
 
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