dot crawl, video noise, or what?

Discussion in 'Archived Threads 2001-2004' started by Haru, Sep 28, 2002.

  1. Haru

    Haru Stunt Coordinator

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    guys, I need some info here. I find that on most DVDs, there is what I would guess is the video equivalent of tape hiss. you can particularly see it on sections of the image that are or smooth, uniform brightness, color, texture, like doors, walls, the sky, car surfaces, etc.
    I would charactertize it as fine dots crawling on the screen and I did some research into dot crawl but what I found was that dot crawl:
    1: is an edge phenomenon, not a surface one. and
    2. is a function of composite video, and is not an issue if S video or component video is used, unless its in the software material itself, which they say is rare.
    Now, I use component video connections, and what I see is a phenomenon that covers the entire picture, not just edges, its very far from rare (in fact its rarely NOT there).
    and here is the interesting thing. I pause the DVD, and the dots stop crawling. I am right now watching Get Shorty, the airport scene, when Yayo Portillo meets Bo Catlett and demands his money. At 23:35, the camera is looking over Bo's right shoulder at Yayo, and in the back ground is the balcony of the upper level. There is lots of this noise/crawl on the surface of this balcony. I just paused it, and the crawling stops and I see that the texture and color of the balcony's plaster surface does not appear smooth, sharp, uniform.
    The surface has very subtle and tiny blotches of dark and light and very subtle, faint variations in the greens and reds across the surfaces. And when I advance one frame, the blotches and color variations change completely. As the thing moves from frame to frame, this noise or whatever it is, changes every time. I am convinced that it is this frame to frame shifting of this noise that appears as that crawl on the screen.
    The question is, can I get rid of it by using a better player? or is it in the software? if it is, why don't they get rid of it?
    I think I am going to go through my collection of DVDs and see if there are ANY that are free from this phenomenon.
     
  2. Paul Clarke

    Paul Clarke Supporting Actor

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    Sounds like a form of color field noise. Try taking the color down a notch at a time to see if the effect lessens or disappears. If it does not, try reducing the contrast and/or brightness to see if that has any effect.

    What is your display? What is your DVD player?
     
  3. Haru

    Haru Stunt Coordinator

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    The display is a Mitsubish WS-46807 HDTV, the DVD Player is a cheapie Sony DVP-S315. I am using this DVD Player only temporarily, but I've noticed this conditionwith most other DVD Players that I've had in this system....

    I'll give what you suggested a shot......
     
  4. RobertSchaez

    RobertSchaez Stunt Coordinator

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    Is it possible that it is the particular disc? Maybe the noise is in the original analog print or the transfer process to digital. I have Caddy Shack on DVD that seems to have a little noise on it, but it's from using a slightly beat up master for the transfer.
    R
     

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