Samsung LN40B550 dark scenes (only) no contrast

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  • mathog
    Badcaps Legend
    • Mar 2010
    • 2655

    #1

    Samsung LN40B550 dark scenes (only) no contrast

    We have an LN40B550 Samsung LED flatscreen and for some dark scenes, in some shows, there is practically no contrast. Ironically "Blacklist" is particularly prone to these. The thing is, in general terms, the color and grey scale calibration is perfect. When a grey scale image is fed in from a laptop through the SVGA port it is perfect. Similarly when this set of video test patterns is fed in through an HDMI connection from the bluray player (which has a youtube interface)

    https://www.youtube.com/watch?v=zTfGuO9chAk

    that is perfect too. These test images have a full range of greys in them though, from full black to full white.

    The issue seems to be that when a scene only uses the bottom 1/8th or 1/16th of the available grey scale range the contrast flattens out to nothing. Presumably some TVs must be able to render these better or they would never broadcast these sorts of scenes.
    These are being viewed in a dark room, so our eyes should be able to adjust to that range and see a reasonable amount of contrast even on that limited range. Which leads me to believe that the inherent contrast which was broadcast is being squished for some reason.

    Is there some control that can be used to address this issue? The standard contrast/brightness are not going to do that, because those are already correct for the whole gray scale.

    Current picture settings are:

    mode: movie
    backlight: 5
    contrast: 50
    brightness: 57
    sharpness:20 (greyed out)
    color:50 (greyed out)
    ting (G/R): G50/R50 (greyed out)

    advanced settings:
    black tone: off (greyed out)
    dynamic contrast: off (greyed out)
    gamma: 0
    color space: auto (greyed out)
    white balance (defaults)
    flesh tone :0
    edge enhancement: off

    Picture options:
    color tone: normal
    size: 16:9
    Digital NR: auto (greyed out)
    HDMI black level: low
    flim mode: off (greyed out)

    Suggestions???

    Thanks.
  • Alastair E
    Chief Womble
    • Mar 2013
    • 1963
    • U.K.

    #2
    Re: Samsung LN40B550 dark scenes (only) no contrast

    Try BL = 8,

    Cont at 80-85,

    Bright to 45-50,

    Colour to 40
    TELEFIX

    How PLASMA SCREENS WORK, X-SUS and Y-SUS what they do--
    http://www.irf.com/technical-info/appnotes/an-1088.pdf
    PLEASE DO NOT EMAIL ME PRIVATELY FOR REPAIR ADVICE. QUESTIONS BELONG ON THE FORUM!

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