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  1. #1

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    Quick reflection density question

    Hi - what is the reflection density of middle grey/zone V. I guess let's assume 18% grey for middle grey for now.

    Thanks

  2. #2
    Bill Burk's Avatar
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    Around 0.75

  3. #3

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    Just to be clear - you're talking about reflection (paper) density, not transmission (negative) density, right?

    Thanks

  4. #4
    Bill Burk's Avatar
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    Yes, the math is the same I think...

    Just to confirm though, I fired up the densitometer and measured the 18% gray card in an old photoguide.

    It read exactly 0.75

  5. #5

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    Quote Originally Posted by Michael R 1974 View Post
    Hi - what is the reflection density of middle grey/zone V. I guess let's assume 18% grey for middle grey for now.

    Thanks
    If it's 18% reflectance then the density is .75

  6. #6

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    Thanks for the help, guys.

    Michael

  7. #7
    Helen B's Avatar
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    For reference the formula is

    Reflection Density = log10(incident/reflected)

    so for 18% it is log10(100/18)

    Best,
    Helen



 

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