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Color vision

  1. May 17, 2005 #1

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    I'm not sure if this is the right forum for it, but I had a few questions about how color vision works. I know that mixtures of pure colors look like other pure colors. For example, some mixture of pure (monochromatic) green and blue looks like pure yellow. So for a given color, are there an infinite number of different mixtures of colors that look the same? How would you go about finding the frequency of a color that a given mixture of colors corresponds to? And how about converting a frequency to an RGB value?
     
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  3. May 17, 2005 #2
    are you asking how the visual system responds to different colour frequencies or how
    these colours are made up in teh physics sense?
     
  4. May 17, 2005 #3

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    I'm saying, given a certain mixture of photons of different wavelengths that are hitting your eye (eg, 30% at 500nm, 45% at 600nm, and 25% at 700nm), what is the wavelength of monochromatic light that would look the same? Or is there not always one? And how do you convert wavelength to RGB values?
     
  5. May 17, 2005 #4
    again: so your asking how does the visual system interprets light then? because converting from light to RGB values is a cathode rays thing)
     
  6. May 17, 2005 #5

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    I don't see what your confusion is. For example, if I wanted to see 500 nm light on my computer screen, what would I set as RGB values in, say, MS Paint.
     
  7. May 17, 2005 #6
    my confusion is are you asking the Neuropsychology Method OR the mechanical Method

    What the actual Eye sees and how MSPaint/CRTs make color are different.
     
  8. May 17, 2005 #7

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    I just want to know how mixtures of light look to the human eye. I don't understand how else you could take my original question. For example, you might say something like:

    Light made of 75% 500 nm and 25% 600nm, according to this formula ....... would look the same as 518nm light.
     
  9. May 18, 2005 #8
    Because the visual system may not be as simple as "formula" as 500nm = 501nm...the visual system is more complicated then CRT tubes...go pick up a standard neuropsychology book look up the section on teh visual system: see how the cones detect color(3 types) then proceed to V1 to V3 OR V4...look up the concepts of Constancy & Intensity.
     
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