Dithering effect

Discussion in 'Archived Threads 2001-2004' started by Nick Fiore, Oct 17, 2001.

  1. Nick Fiore

    Nick Fiore Auditioning

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    I have a Sony High Scan 53. I have noticed that while watching either DVD's or satellite TV I get a dithering or gradating effect in my backgrounds. The effect occurs when going from light to dark areas in the picture. I can physically see divisions of color gradations in the areas of the picture when going from the light to dark areas. Does anyone have any experience with this effect and how to resolve the issue? Is it my TV or an adjustment that I can make?
     
  2. Dwight Amato

    Dwight Amato Stunt Coordinator

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    Nick, I think that is just how it is. I just got myself the 47" Panny 2 days ago and I've been watching lots of movies on it. I notice that walls in movies are not always a solid color but definately has some 'dithering' going on. I am not running a progessive scan DVD player yet. I think this is just the way MPEG encoding works, and that you can't notice it on smaller TV's. Maybe I'm wrong though...
     
  3. Jeff

    Jeff Supporting Actor

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    This is mainly due to compression artifacts and really varys with DVD's. I find it more difficult to see them on many of the DVD's released in the past year. On older DVD's, and even on some recent ones, I can spot them when I'm close to my Sony Wega.
    Jeff
     
  4. MarkDesMarais

    MarkDesMarais Stunt Coordinator

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    Dithering is actually a little different. If you want color Y, but all you have is X and Z, if you show that pixel as X one frame, then Z the next, the viewer's eye will see Y. You can do it spatially too.
    I think most people call the effect you are observing "banding", I believe it results from not enough color depth somewhere in the process. I certainly see plenty of it on Dishnetwork- it can be pretty distracting.
    Markd
     

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