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Discussion Starter #1
Have a Panasonic AE700, prolly 700 hours on it's second bulb (first one went out at 500...
). Anyway, it's connected via component to my Comcast HD-DVR cable box, and through VGA to my computer.



Watched a 4x3 movie last night on digital cable (Braveheart, so ~ 3 hours). When I flipped the input over to VGA for my computer (which is displaying 16x9 1280x720), I noticed the sides of the destop had a very distinct blue tint to them, right where the 'black bars' were from the movie. This is the first time I've ever seen anything like it. After about 30 minutes of PC usage, the 'bars' seemed to go away, and the screen was normal again.


However, during the PC usage, I watched a 20 minute video in Windows Media Player, but not fullscreen. After closing WMP, I noticed the same blue tinted 'box', but this time the same spot that the video was playing in. The rest of the screen, that was only displaying static images, was unaffected.


Again, this eventually went away, but it's very concerning. The blue-tinted boxes and bars were visible across all inputs, so it's gotta be something in the projector itself.
 

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Be VERY careful. What people (like me) are finding out the Panny 700--LCD Burn in IS real. The idea that LCD's can't burn in is a complete myth. I ruined my 700 this way. In fact, I just got done talking to the repair shop, and he said my blue LCD panel has been permamently damaged from excessive 4:3 use. It exhibits the exact same symptoms as your projector, but the bars don't go away.


I don't know what to do now. I love my projector, and the rebate on the 900 runs through today so I'm thinking of upgrading to the 900 and just not using 4:3 mode on it. But EVERYONE BE CAREFUL--extended 4:3 mode viewing WILL RUIN your LCD projector, at least the Panny 700.


Does anyone think I could get any traction with Panasonic on this issue? I am outside of the 1-year warranty by about 4 months.
 

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I used to think that LCD pannels are immune to burn-in. Not anymore. The LCD screens at the internet cafe that i'm sitting right now suffers from the same symptom. This is most allarming. Even the manual of the 900 i'm having says it. And let's say that, OK, we're not projecting 4:3 in our pj. What about 2,35:1? Those movies have large black bars. Isn't there danger of destroying the panels? What puzlles me though is why my old Sony 400qm with more than 4000 hours didn't have any problems with extensive 2.35:1 projecting...
 

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Yes, I would assume that 2:35:1 is likely to eventually burn in as well. Very disturbing.


I just ordered a Panny 900 to take advantage of the $400 rebate. But my usage is going to be MUCH different with this one. No more 4:3 TV watching for me. And less usage in general to avoid the high bulb price.
 

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I don't know why Panasonic projectors seem to have this. My (unreliable) memory seems to recall far more stories about Panny LCD panel problems than any other yet they use the same panels as Sanyo, Hitachi and Epson. Do they have a consistent panel cooling problem in the AE range?
 

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Discussion Starter #6
Did a few more tests last night - What I find interesting on mine, is that it take an incredibly short time to cause these "ghost" images (seems to be only affecting the blue panel).


For instance, my background pic on my desktop is mostly greys, with two darker shapes in the middle. After leaving the PJ on the b/g image for only 10 minutes(!), I could see the two shosted shapes when I switched to another completely differen screen. Why would this be happening so fricken fast?!? How could the image be burning into the panels so quickly (if that's even possible)?
 

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All of my problems were in the Blue panels as well. There was a very VERY slight darkening of the green panels that I would never have even noticed had the blue pannels not been damaged. The blue ones were the ones that were significantly darkened.
 

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What out, as the eyes are also a factor in the short tests.


Just look outside a window and they turn away and close your eyes - the window still there as a colored ghost on your retina.


Or read a text for 5 minutes, white letters on black screen, and look away - you'll see horizontal stripes on your eyes for minutes.


I'm of course not saying the burn-in isn't real; just stating that eyes are strange things as well



Reminds me of that page they used to fax around in the 90's - you had to stare at it for a minute, then look at a white wall - you could see Jesus in a black circle, very disturbing
 

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Very strange. I have a 700 with over 1700 hrs on it. 2nd bulb, the first blew at 1400, natch.


I watch a good deal of 2.35 and 1.33 material -- it is rare for me to find movies or anime in 1.78.


Havn't noticed classic burn-in, where there is a solid demarcation, a line if you will.


What I do notice is this projector has pretty horrible color uniformity, doesn't matter what format you're watching. Most noticable on black and white movies. The right edge of the image (be it widescreen or square) has a blue tinge to it, the left has a reddish tinge to it.


But I wouldn't catalog this as 'burn in'. Just as "horrible color uniformity'


I suspect what I"m seeing is some sort of panel or optical misalignment.


At this point, I don't care -- as soon as c2fine hits the market, I'm getting one, and will retain the 700 as a cold spare.
 

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Is the projector displaying image retention (temporary) or actual burn in (permanent)?
 

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Quote:
Originally Posted by JamesAHall /forum/post/0



Does anyone think I could get any traction with Panasonic on this issue? I am outside of the 1-year warranty by about 4 months.

If you bought this item with a major credit card, you will probably get your money back for the projector. Almost all cards double your warranty up to one year. American Express does everything over the phone, with no paperwork. All you have to do is get an estimate. If the item is unrepairable, your money is prompty refunded. All new purchases are covered. This is one of the most valuable and underused CC benefits.


MY pany HT-900 home theatre broke and the entire price was refunded after the repair shop said it was hopeless.
 

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Discussion Starter #12

Quote:
Originally Posted by DB2 /forum/post/0


Is the projector displaying image retention (temporary) or actual burn in (permanent)?

That's a much better way of wording it than I could come up with. It's definitely temporary in my case. The ghosted images are 'retained', for lack of better word, for several minutes (~10) before they aren't noticable anymore.
 

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I'll check into that LCDGuy. Thanks!


DB2--this is definitely permanent damage. I tried running full-screen white (as suggested several places online to fix LCD damage) and it seemed to reduce the burn-in by a little bit, but not enough to call it fixed by any means.
 

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There's supposed to be a pic shift facility in the secret menu which when turned on alters the image by one pixel every minute ( at least i think its one pixel ) anyways the purpose of this is to stop screen burn in..... perhaps yours is turned off in the secret menu.


I'm on my second bulb and approximately 1300hours of use and i haven't suffered from this problem ( just dust blobs on the panels which i have cleaned out myself )
 

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Altering the picture by one pixel every minute isn't going to help. The black 4:3 bars are WAY wider than one pixel. Even if you shifted 10 pixels, most of that area will always be showing black.


I did some calculations, and I was probably up over 2000 hours, about 2/3rds of which was 4:3 watching, when I first saw the problem. So all of you people who are watching a ton of 4:3 but haven't seen anything, be warned--it might not show up until you've used the projector for a while. I didn't notice mine at all, and then one day it was there clear as day and horribly distracting.
 

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Just wondering... How many hours of continuous use can cause the problem? I mean, if you use the pj only for 3-4 hours to watch a movie, isn't mutch. Even with crt pjs that wouldn't be a problem. Maybe the problem can be caused only if you overdo it. More than 6-7 hours maybe? Does anyone have noticed it within the time limits of a movie? THAT would be most scaring...
 

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Quote:
Originally Posted by JamesAHall /forum/post/0


Altering the picture by one pixel every minute isn't going to help. The black 4:3 bars are WAY wider than one pixel. Even if you shifted 10 pixels, most of that area will always be showing black.

My understanding of how it works is that the whole image shifts by one pixel thus this avoids screen burn... so every single pixel onscreen shifts unless the facility has been turned off in the secret menu.
 

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Could burn in be a heat related problem? It seems to my non electrical engineering mind that anything that increases the heat of the PJ could affect the panels too and not just the life of the bulb. This would include ceiling placement (it's warner up there) and PJ placement near anything that blocks its air flow. I mention this only because most of us don't experience burn in so I think it must be caused by variations in parts or the way the PJ is used.
 

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Quote:
Originally Posted by FoxyMulder /forum/post/0


My understanding of how it works is that the whole image shifts by one pixel thus this avoids screen burn... so every single pixel onscreen shifts unless the facility has been turned off in the secret menu.

Again, how would that help with the black bars? I can see how it would help with static text or images from a video game. But the black bars are very large. Even if you shift the image around, most of the pixels showing the black bars will STILL be showing the black bars. If the problem stems from a particular pixel showing black too much of the time, then shifting the black bars around a pixel won't help.


Still, I'm curious--where is this magical setting displayed? I certainly never turned it off intentionally, nor have I heard anyone else talking about it. I've heard of that kind of thing on plasmas, but not on an LCD projector.


I'm still running my damaged 700 until my 900 shows up, and I'm seeing more and more strangeness from my blue LCD panel. The green and red seem to be fine, but the blue one is all messed up now. I also noticed that my flicker settings, which I had held constant for 8 months, all of a sudden needed to be drastically different for blue (way, WAY higher than it used to be, by almost double). So now I'm wondering if somehow my blue LCD panel just was defective and went bad on me. Maybe the burn in I'm seeing only happened because the panel was defective? Who knows. I used my PJ a lot more than most people, so we should know if there is an inherent failure in the 700's LCD blocks in the next year as other people catch up to my usage amounts. Hopefully I just got a lemon and everyone else will be fine.


In the meantime, I am going to be a lot more careful with my 900 when it shows up.
 

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Discussion Starter #20

Quote:
Originally Posted by JamesAHall /forum/post/0


Again, how would that help with the black bars? I can see how it would help with static text or images from a video game. But the black bars are very large. Even if you shift the image around, most of the pixels showing the black bars will STILL be showing the black bars. If the problem stems from a particular pixel showing black too much of the time, then shifting the black bars around a pixel won't help.


Still, I'm curious--where is this magical setting displayed? I certainly never turned it off intentionally, nor have I heard anyone else talking about it. I've heard of that kind of thing on plasmas, but not on an LCD projector.


I'm still running my damaged 700 until my 900 shows up, and I'm seeing more and more strangeness from my blue LCD panel. The green and red seem to be fine, but the blue one is all messed up now. I also noticed that my flicker settings, which I had held constant for 8 months, all of a sudden needed to be drastically different for blue (way, WAY higher than it used to be, by almost double). So now I'm wondering if somehow my blue LCD panel just was defective and went bad on me. Maybe the burn in I'm seeing only happened because the panel was defective? Who knows. I used my PJ a lot more than most people, so we should know if there is an inherent failure in the 700's LCD blocks in the next year as other people catch up to my usage amounts. Hopefully I just got a lemon and everyone else will be fine.


In the meantime, I am going to be a lot more careful with my 900 when it shows up.

I agree about the pixel shifting - doesn't sound like it even truly exists, nor would it help if it did.


I certainly hope my unit isn't showing the early signs of having the same problem as yours. I'd hate to be forced to upgrade. I however won't be buying Panasonic again.
 
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