Horizontal lines in picture

Discussion in 'Displays' started by Gary Shipley, May 16, 2004.

  1. Gary Shipley

    Gary Shipley Second Unit

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    I have a Panasonic RP91 dvd player and a Sanyo PLV-60 projector. I have noticed some horizontal lines in areas of the picture(such as flames on torches). The RP91 has a variety of settings for the picture mode(normal,soft,fine and cinema). They suggest the cinema setting for viewing movies. I've found the only way I can use the cinema setting is to shut off the progressive scan on the RP91.This eliminates the lines. The only other way to get rid of the lines is to leave the progressive scan on and use the fine setting for the picture mode. I also have the ability to shut off the progressive scan on the projector. By having the progressive scan on,on both the dvd player and the projector, am I to assume that one is canceling the other out causing the horizontal lines? If that is the case,
    which one should I shut off the progressive scan on?
     
  2. Allan Jayne

    Allan Jayne Cinematographer

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    How long and how thick are the horizontal lines? What color?

    Occasional very thin usually short discolored horizontal lines at a top, bottom, or diagonal edge of color patches suggest "the chroma bug" in a DVD player although I am told the Panasonic RP91 does not have this problem. Some of the poorer progressive scan conversions hide the chroma bug. Proliferous uniformly spaced thin horizontal lines at the left and right edges of moving objects are a sign of progressive scan conversion poorer in a different way.

    Turning off the progressive at the player generally causes the projector to automatically turn its progressive conversion on, and vice versa. Whichever you choose depends on which looks better.

    What happens if you shut off the progressive on the projector manually?

    Alternatively, does your projector have a requirement as opposed to an option that you turn progressive scan on or off to match the source?

    Video hints:
    http://members.aol.com/ajaynejr/vidbug2.htm
     
  3. Gary Shipley

    Gary Shipley Second Unit

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    Thanks for the info Allan. The horizontal lines are the thin lines at the left and right edges of moving objects. I could'nt find any information in the projector manual about needing to have the progressive scan on. After a few tests, I decided to leave the progressive scan on, on both pieces of equipment, and set the picture mode on fine. All in all, if I do decide to shut off the progressive scan on one of the two, it will be the dvd player which gets the cut. The picture quality seems to be better with the projector providing the progressive scan than vice versa. Thanks again
     

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