optimum luminance value???

Discussion in 'Displays' started by Carmine, Sep 8, 2005.

  1. Carmine

    Carmine Agent

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    i've recently been tweaking my Sony 55XS955 LCD RPTV & just had a quick question. I've been calibrating my grayscale using a Spyder2 colorimeter & was just wondering what the optimum luminance output value should be at 100 IRE in ft.L.

    thanks very much for all your help guys.
    Carmine.
     
  2. Michael TLV

    Michael TLV THX Video Instructor/Calibrator

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    Michael Chen
    Greetings

    No real light output value for digital displays. For RP CRT sets ... it was 20 ft-l based on a 100% white windowbox.

    On digital displays ... you want the light output as high as possible to get maximum dynamic range in the image ... but you pay attention to the following three rules:

    1. No white crush.
    2. No discoloration of the grayscale sweep.
    3. 100% White Windowbox does not hurt your eyes to look at.

    Regards
     
  3. Carmine

    Carmine Agent

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    Once again Michael, i have to say thank you very much. You always respond to my questions ASAP.

    thank you again!!!
    Carmine.
     
  4. ChrisWiggles

    ChrisWiggles Producer

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    Michael is absolutely correct, I just wanted to add in that if your digital display is too bright after you maximize black and white points correctly (just avoiding 1 and 2) then you should physically alter the brightness by using an ND filter or a lower-gain screen. Lowering the white level is acceptable temporarily, but doing so is reducing the contrast range below ideal. Using a different screen or a filter maintains the same idealized on/off CR range, but reduces the light output overall. Lowering the white level will reduce the white point, while black remains fixed and immovable, thus reducing the CR range of your display below its capability.

    This applies to digital displays, NOT CRT based displays.
     

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