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Discussion Starter · #1 ·
I have had my 37" Panasonic plasma for 6 months. During that time it has been in use for about 3-1/2 hours per day. i.e., a total of approximately 630 hours.


95%+ of my viewing has been SD broadcasts at the 4:3 "normal" setting with the sidebar brightness control set to "off," which gives black sidebars. The rest has been DVD's or letterboxed 4:3 images at full screen. Picture controls are at factory defaults.


If I look closely at a blank white screen, I can see a very faint demarcation between the side bar areas and the center of the screen, which I doubt a casual viewer would even notice. There is no such demarcation visible when watching regular TV, even for wide expanses of sky or other bright, uniform images.


I might be able to reverse this "burn in" (if you can even call it that) by leaving the screen blank white for a few hours, or perhaps setting the side bar control to its brightest and leaving the center black for a while. However, since there is no visible effect for normal viewing, I am not going to bother trying any fixes.


I have turned the sidebar brightness control "on" and to its darkest setting, which is a dark gray. I liked the black sidebars better, but found it easy to adjust to the gray after a few hours' viewing. Will check again in another 6 months to see if this has made any difference.
 

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I just now remembered about this friend's old computer monitor she was using. It was a nice one, but couldn't go over 640x480. The tube was flat and there was a fan inside to keep it cool. Well, in order to adjust the size, you had to stick a small screwdriver in the little holes to adjust. The way the monitor was calibrated was that the image was in the center of the screen with black borders all the way around. So, I fixed that for her and the middle is dark, and the borders are a lot brighter. Of course. That monitor was probably over 10 years old. I never even thought to THINK about that monitor until now. So. I do believe it. Plasmas and CRTs, especially Projections, WILL burn in over time if the only a portion of the screen is used up. I understand why you watch 4x3 with the side bars. You want it in OAR and not stretch or zoom. I personally hate the stretch mode the most. If you get some burn-in in the 4x3 area. Then change the black bars to gray for a while to help equalize it. I've looked at a few widescreen TVs in the stores where they were showing 4x3 material is STRETCH. They even had the Pan and Scan of SHREK on there in STRETCH! I'm like, WTF, and made the guy get the widescreen disc. Well. Good luck trying equalize that burn in. Plasmas are really cool and all that, but, to save myself the burnin, I'm shooting for either LCD or DLP.
 

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Steuert: The white sceen is pointless. Running the bars in the lightest color with nothing in the middle would almost certainly equalize the burn in over time.


As you say, it may well not be worth it given how little the effect is there. It's also worth nothing that given the logarithmic decline in phosphor brightness (per Trainerdave), it's likely that the next 6 months will be more forgiving than the first 6 months. I'm not guaranteeing that, but it is worth being optimistic.


Mark
 

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The only thing that could fix such a thing is a white noise filter (you can probably build one using Visual Basic) through a computer, running overnight.


The areas where the white noise should be active is the region around the sidebar lines.


Sounds like a project for someone...
 

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The Pioneer has an inverst mode. I think the Panny does.
 

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If you never view anything with sidebars will you defeat the burn in problem?
 

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I have to say I was -- in the first hours -- filling the screen ALL the time. Now that it's "broken in", I allow the 4:3 bars occasionally -- although I almost never need to as Wide mode on the Pioneer simply doesn't bother anyone -- and the 2.35:1 top-bottom bars without really any concern when they appear on some DVDs and widescreen SD stuff like West Wing.


Mark
 

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So 600 hours of 4:3 viewing can cause burn in?


I thought pixel life was in the 10,000+ range, so just 6% into its life there is a small, but significant degridation in pixel brightness?
 

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ADent (Arthur Dent?!),


Each second of use on a pixel causes a infinitesimal degredation in pixel brightness.


Burn-in is caused by the fact that different pixels are being used (used= bright points) differently. Normally, pixels average out to be used pretty much the same (although the center of the screen often gets used a bit more).


Overall, it is only important when the same pixels keep working and others are kept off. If there's also a distinct difference between them (e.g., 4:3 area lines), the edge of that line will be quite visible after a while. I would say that it can start happenning even before 600 hours.


Overall, if you MOSTLY watch full screen (either stretched, or wide modes), and occasionally (e.g., when watching specific shows, or DVD movies) have sidebars or letterbox marks, you will not see any problems.


Another way to reduce this problem is not to use black letterbox or sidebar blocks. My NEC plasma has the option of changing the shade of these bars. A mid-level grey will reduce the problem somewhat (although it's not recommended over a long period of time). The purpose of all of these is to create UNEVEN wear, that's largely invisible, instead of EVEN wear (= burn-in).
 

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Why would people opt for sidebars after buying such a great, bright big display?Thanks for your input Ofer.Im about to go with the 433cmx and I hope the wide mode for fitting sd tv to the plasma doesnt look too obvious.Do you know if the 433 allows for different stretching modes and if those dvds that still put small bars on the screen can also be made to fit the plasma? thanks matt
 

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Quote:
Originally posted by mattg3
Why would people opt for sidebars after buying such a great, bright big display?
So we don't watch images that have either:


a) uniform distortion of 25% in width


or


b) progressive distortion of up to 50% in width


or


c) cropped 25% in height


The same reason I can't watch anything on TNN or Oxygen or Trio, really.
 

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Discussion Starter · #16 ·
I agree with Stormsweeper. It surprises me that some of the same people who fuss about the evils of pan and scan - "Oh, you're not seeing the picture as the director intended, tsk, tsk!" will put up with the various weird distortions that plasmas use to expand a 4:3 image to fill a 16:9 screen. Just because you have a big screen doesn't necessarily mean you have to enlarge every image to fill it to the edges, regardless of the mess such manipulation makes of the picture.


I somehow doubt that many directors intended for the top and bottom of their pictures to be lopped off, to have all the actors turned into humpty-dumpties in "wide" mode, or to have the actors expand and contract in size as they move across the screen in order to "justify" the image.
 

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This thread has got me thinking-


Does anyone make, or has anybody here used- physical (like black felt) sidebars for 4:3 viewing?


Seems like if your viewing is 80/20 TV/DVD it might make sense just to keep a physical masking on that you can pull off for DVD watching.


Tufnel
 

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Or how about a black magic marker? ;-)
 

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I want to point out that the thin lines of burn in, as opposed to the whole "black bars" worth of burn in, would be visible unless you perfectly wear down not the edge of the burn-in zone vs. the 4:3 area. In other words, Ofer's post above about white noise or somesuch is relevant if you want not just no bars burned in, but no lines burned in. That's why the screen saver idea is only so useful.


That said, I think it's true that you are better off trying to keep your use of bars down in general, without mania/paranoia. Note that grey bars (especially medium-to-light grey) will minimize bar burn in, but do nothing -- in my opinion -- to minimize thin-line burn in.


Also, I again reiterate that I was sure I couldn't watch in "stretchyvision." Pioneer's Wide mode and Panasonic's equivalent changed by tune. Pioneer's is even better than Panasonic's because it actually enlarges the vertical just a tidge, distorts the middle hardly at all, distorts the edges a wee bit, and then I believe chops off the sides a tidge.


I agree its distortion, but really, given the PQ DirecTv is sending me, I hardly mind "mangling" their picture. Come on, it's not exactly art with all those artifacts anyway.


Mark
 
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