Negative logic?

Discussion in 'Color: Film, Paper, and Chemistry' started by JD Morgan, Dec 5, 2004.

  1. JD Morgan

    JD Morgan Member

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    Anybody ever change the markings on their head to RGB so they didn't have to think backwards?
     
  2. mark

    mark Member

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    I have a stupid question -What do you mean?
     
  3. JD Morgan

    JD Morgan Member

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    Like when you decrease yellow value in filtration the inverse occurs to the print. So if you are thinking about your output (print) it is unnatural to have a dial marked 'Yellow' whose respective meter is directly impacting blue in the sense that decreasing value decreases blue NOT yellow.

    Why is it done that way rather than corresponding to the final result?
     
  4. Nick Zentena

    Nick Zentena Member

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    RGB heads are different. I think Beseler had at least one head with RGB filters. The process is additive. The CMY is subtractive.

    Using a yellow filter with B&W film will reduce blue. If you're used to thinking of filters and colour with B&W then it's a little easier.

    But after awhile it become second nature to lower yellow when you want more.
     
  5. stevewillard

    stevewillard Member

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    Negative logic or subtract color logic is not that hard once you get used to it. I have too simple rules for managing color changes:

    1. Add or subtract a primary then add or subtract the complement on the color head, respectfully.

    2. Add or subtract a complement then reverse - subtract or add, respectfully.

    Simple.