Change colour temp with grayhawk screen?

Discussion in 'Projectors, Screens & Video Processors' started by Jules, Jun 10, 2002.

  1. Jules

    Jules
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    Hi,

    I've been playing around with my VW11HT since the arrival of my Stewart Grayhawk screen 2 weeks ago, and have noticed a shift in colour temperature compared to my previous white screen.

    Blacks and shadow detail are miles better (chalk and cheese), but the 'low' temperature now screams GREEN, GREEN, GREEN ! It just looks wrong.
    It was always a little green before, but not quite so obvious.

    I know most people use 'low' because its said to be accurate for NTSC signals, but does this rule change when using a grey screen. Would 'high' be more accurate.

    I've fiddled with the custom temps in the service menu, but frankly I'd never use any of them because I'd always know they couldn't possibly be right.... I'm colour blind.

    Any opinion or advice would be very much appreciated.
    Can anyone help?

    Thanks
    Jules
     
  2. Gordon @ Convergent AV

    Gordon @ Convergent AV
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    The geyhawk shifts greyscale to make it hotter I believe. That means more blue usually. The only greyscreen I have measured so far was a VuTec greydove and the difference between the light hitting it and being reflected back was 500-700k I think if I remember correct. I think greyhawk is similar from measurements taken in the states. Firehawk is only about 150K off so much better in this regard.

    You could do a user setting with same bias and gain as low Sony setting and then turn down the green in the low areas until it looks more acceptable to you. Make sure you store the setting before going out of the menu though....

    Gordon
     
  3. Jules

    Jules
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    Thanks Gordon.

    So 'high' would be worse then as it is introduces its own blue tint.
    That's useful info, thanks!

    I've just dropped the green gain by about 10% using all other settings just as they are in 'low'.
    And apart from a slight drop in contrast, I think its ok?

    I know I could boost the red & green levels instead to make up the difference, but I worry that the bias settings would then be wrong. I don't understand these things, so I'll just use your good advice and stick with it.

    Thanks again
    Jules
     

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