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Is TV ready for Plasma?

Discussion in 'Plasma TVs' started by swarrans, Nov 9, 2002.

  1. swarrans

    swarrans
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    OK, maybe a misleading title, but what I mean is...
    Any prospective plasma buyer like myself (and, I'm sure existing owners) must be frightened to death about all the posts about screen burn, logos, display life etc.
    As there is still loads of television output in 4:3 mode which will result in vertical black bars if it's shown "correctly" are TV transmissions ready for plasma? Just how "bad" for plasmas versus CRTs is it to show black bars on a regular basis.

    There again, even when "all" TV transmissions are in 16:9 we'll still have (horizontal) black bars when showing 2.35:1 DVDs and other material - so is the question really "is plasma technology ready for TV?"

    For the "techies" out there is the issue of screen burn and permanent damage an unavoidable product of plasma technology, or is it something that we can expect to get better it time?

    Finally, I suppose before I lash out a minimum of £3,000 on a new screen what I really want to know is - is this a real problem for a "normal" watcher, or am I worrying too much!

    Regards,

    Simon
     
  2. EvilMudge

    EvilMudge
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    With a digital source such as DVD or SKy, so long as you have a well shielded high quality lead, and you don't set the brightness of the display too high then black bars are not a problem. Most screens when confronted with a dark pixel will simply switch it off.
    Far more worrying are those stupid channel logos which everyone on this forum hates AFAIK. Unfortunately Plasma's have an intrinsic problem with these because the pixels stay illuminated for a lot longer than with a conventional TV.
     
  3. Paul D

    Paul D
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    I think screenburn in plasmas is a very real, but "over hyped" problem.

    Like most CRT projectors, very bright logos and 4.3/2.35 (black borders) ratios on a 16.9 screen can if left long enough create a wear pattern.

    Almost any light source degrades in brightness overtime.
    LCDs and DLP panels are either transmissive or reflective devices, so although their light source "does" degrade, it is easy to replace.

    The problem known as screenburn, is exessive/premature wear on that part of the display. When a white screen is shown, these worn parts will not be as bright etc.

    So leaving a bright logo on screen will be more damaging(or a shorter time needed for wear) than watching a letterboxed (or 4.3) image, since the letterboxed(or 4.3) image will vary in brightness due to the moving picture shown etc. But given long enough even these borders will show the difference in wear (in the "black borders" case - less)etc.

    Real screenburn (ie not wear) is caused by driving the plasma pixel or CRT tube far to high.
    Try running a 12 volt bulb at 24 volt and it will last well less than half the running/wear time (if not blow almost straight away)
    This type of burn not only wears out the pixel/tube very quickly, but can actually cause a browning "burn", making the problem stand out even more.

    So back to the question about plasma "screenburn"!

    So how long can a bright white "Sky" logo be shown before you begin to burn/wear the display?
    Some people in "the know" seem to think you would be safe for up to 48 hours continous "logo" showing. After that they seem to think you are on dangerous ground.
    Again the exact time would depend on how hard you drive the contrast on the display etc.
    Another variable is all day "daily" watching, ie Sky News bright red logos being one of the channels to avoid all day daily viewing.
    (SKY PLEASE NOTE....YOU WILL LOSE VIEWERS IF YOU CONTINUE WITH THESE UNWANTED LOGOS!)
    Why don't Sky at least have very faint or temporary logos that appear at the start and end of a program?
    Or since they dictate the design of their digi boxes have the logo showing on the digi box it's self?

    Manufacturers print the warning to cover their "behinds". They know logos are unavoidable, as they are an everyday feature of "British" digital viewing. I'm sure they have done extensive testing, but prefer to just play it safe.

    So i'm NOT saying screenburn doesn't exist, but with normal "varied" viewing it shouldn't be much more of a problem than a regular CRT TV.
    Screenburn is now mostly a corporate "fixed image" (ie showing the same thing daily) problem.

    Mind you i will still press "back up" on my sky remore everytime i see that red dot!:D :p
     

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