Dismiss Notice
Attention AVForums app / Tapatalk users
Sadly GDPR means that, from 25th, we can no longer offer access to AVForums via the branded app or Tapatalk.
Click here for more information.

aaaaarrgg!!!! Dead pixels?

Discussion in 'Projectors, Screens & Video Processors' started by beecee, Aug 5, 2004.

  1. beecee

    beecee
    Well-known Member

    Joined:
    Dec 8, 2003
    Messages:
    2,277
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    87
    Location:
    Kirkcaldy, Fife
    Ratings:
    +451
    well one green one top right hand corner, but what i dont understand is how?

    (and i only noticed it becase of a damn fly sitting on my screen! if i haden't got up to flick it off i probably would not have noticed it, now i am allways looking.)

    if there are 3 panels (red, green and blue?) how come i get a green pixel, what are the chances of both the red and blue pixel sticking at the same place at the same time? in order for just the green one to be seen. or is that not how it works.

    can some one explain??? :confused: :confused: :confused:
     
  2. LV426

    LV426
    Administrator Staff Member

    Joined:
    Jul 14, 2000
    Messages:
    13,425
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    Somewhere in South Yorkshire
    Ratings:
    +5,824
    It's not how it works.

    LCD pixels are naturally transparent (light), and only opaque (dark) when they are energised (working). So, normally, when they fail, they fail light, and the backlight shines through. If it's on the green LCD, then the light is tinted green as it passes through.
     
  3. beecee

    beecee
    Well-known Member

    Joined:
    Dec 8, 2003
    Messages:
    2,277
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    87
    Location:
    Kirkcaldy, Fife
    Ratings:
    +451
    so what happens to the red and blue panels, do they still work? if so they would have an effect on the colour?
     
  4. LV426

    LV426
    Administrator Staff Member

    Joined:
    Jul 14, 2000
    Messages:
    13,425
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    Somewhere in South Yorkshire
    Ratings:
    +5,824
    Not sure about your question. It's highly unlikely that all three (or even two) panels will fail at exactly the same pixel.

    However, maybe this explains it:

    If a green pixel (only) is transparent, then you see green.
    If a red pixel (only) is transparent, you see red (!)
    If a blue pixel (only) is transparent, you see blue.

    If all three are transparent, you see red+blue+green which makes white.
    If blue and green are transparent, you see blue+green which is cyan
    If red and green are transparent, you see yellow

    etc.

    Partial transarency of one or more primary colours in differening proportions gives the full spectrum

    If all are opaque, you see black (well they are never fully opaque, so grey, in fact).
     
  5. dither

    dither
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Think about it this way: it's only a problem when the green pixel is meant to be off. So, you won't see it at all in a big green or white area, because the green was meant to be on anyway. On the other hand if it is in a black area it'll be very noticible all three pixels (RGB) are meant to be off, and it'll show up green. In areas where it was meant to be on a little (say a greeny blue sea) it'll just look a bit more green than it should, so you probably won't notice that as much.
     
  6. beecee

    beecee
    Well-known Member

    Joined:
    Dec 8, 2003
    Messages:
    2,277
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    87
    Location:
    Kirkcaldy, Fife
    Ratings:
    +451
    ahhhh, thanks guys. got it... i probaly wouldn't have noticed it any way but i was watching Blade.

    i can only see it if i stare at it, as i sit pretty far back and have the picture zoomed in, so when i do see it, its tiny.

    still would preffer not to have it :thumbsup:
     
  7. beecee

    beecee
    Well-known Member

    Joined:
    Dec 8, 2003
    Messages:
    2,277
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    87
    Location:
    Kirkcaldy, Fife
    Ratings:
    +451
    well, strange thing happened....

    i watched a film last night and the pixel os okay! its not there anymore. :clap:
    which i am well happy about. is this normal! pixels returning to working order?
     
  8. LV426

    LV426
    Administrator Staff Member

    Joined:
    Jul 14, 2000
    Messages:
    13,425
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    Somewhere in South Yorkshire
    Ratings:
    +5,824
    It's rare, but has been known to happen.
     

Share This Page

Loading...
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice