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Color and Perception

  1. May 26, 2003 #1
    There was a line of debate that was started in the old PFs, but it was never finished, and I'd like very much to continue it.

    The following is the conversation:

    You see, I would reply that all Alexander did was give the Scientific labeling of that which we percieve (color).
  2. jcsd
  3. May 26, 2003 #2
    Color is not a wavelength, else we would not have a seperate and distinct word for the quality. For example, I cannot see the color "infra-red", but I can measure its wavelength and deduce it exists.
  4. May 26, 2003 #3
    Re: Re: Color and Perception

    Good point.
  5. May 26, 2003 #4
    Re: Re: Color and Perception

    What do you mean by "color is not a wavelength?" Infra red is not a color or in the visible spectrum of wavelengths (which I'm sure you know) but color is the range of wavelengths within the visible spectrum that is visible.
    Also, I heard that some people have some sort of condition/mutation where their eyes can detect wavelengths outside of the spectrum where they can see in infra red or something. Anyone know about this?
  6. May 26, 2003 #5
    Color is just a certain quality that our brain assigns to a certain range of wavelengths. From the human perception, infrared or UV are not colors, because the brain is incapable of assinging a color to those waveleghts. But, from the perception of a cat (I beleive cats are able to see UV) ultraviolet would be a color, while from the point of view of an animal that can't see red, red would not be a color.
  7. May 26, 2003 #6


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    I think the important thing to stress is that color is not something "out there". Photons of various energy levels do not actually posses a color themselves, but are simply the physical phenomena that causes the brain to percieve colors.
  8. May 26, 2003 #7
    Re: Re: Re: Color and Perception

    Linguistically color is a quality, not a quantity like wavelength. Thus you will hear people say things like, "My, what a beautiful color of red" but never, "Gee, what a gorgeous wavelength of 435u. In both cases, neither term has meaning outside of the context of how they are used in language. Conceptually, whether or not they are qualities, quantities, or both in the real world is a question for metaphysics.
  9. May 26, 2003 #8
    The Advent of Color

    How about the relationship between the numbers 6, 7 and 8 and a hexagram with the six basic colors -- red, orange, yellow, green, blue and violet -- plotted in accordance with a color wheel, as well as the seven notes of the musical scale? All of which portrays a general "symmetrical relationship."

  10. May 26, 2003 #9
    Re: Re: Re: Re: Color and Perception

    That is why science uses spectrometers instead of: "...But I tell you: it was orange-green with slight turquose haze - not yellow as you wrote".
  11. May 26, 2003 #10
    Re: Re: Re: Re: Re: Color and Perception

    Yes, and that is why science is a human invention. Imperfect human perception led to the development of extremely accurate devices. Go figure.
  12. May 27, 2003 #11

    Yes, but wouldn't that be tantamount to saying something arose out of nothing? Or, does it suggest "something" (perfection) was already there?
  13. May 27, 2003 #12
    It suggests any number of things including the possibility of invisible pixies on our shoulders actually dictating all of our thoughts to us. That's exactly why I bring it up. As bad a mistake as it can be to extrapolate too much on limited information, it can be equally mistaken to assume you already know the answers.
  14. May 27, 2003 #13
    Re: Re: Re: Re: Re: Re: Color and Perception

    Exactly. The less human senses in measurements, the better (more objective) are the data.
  15. May 27, 2003 #14
    Re: The Advent of Color

    Not much relationship because numbers etc here were ARBITRARY assigned by a human, ruining all futher relationships or symmetries which may present there originally.

    In contrast, wavelengths numbers are not arbitrary but mutually related to each other. (Say, wavelength of blue is always about 0.7 of wavelength of red regardless units or devices to measure it).
  16. May 27, 2003 #15


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    Science Advisor

    Greetings !

    My opinion:

    Color is what we observe. It is an ellement
    of our data input.

    The wavelenght of the colors is a scientific
    deduction from the observed data input.

    If there is an additional problem or a point that
    I missed here, please, do point it out to me.

    Live long and prosper.
  17. May 27, 2003 #16
    Re: Re: Re: Re: Re: Re: Re: Color and Perception

    So, if a tree falls in the forest and you have a decebel measuring system set up that no one ever checks on, that is perfect objectivity.
  18. May 27, 2003 #17
    Re: Re: The Advent of Color

    What about "pigmented" colors, which is what they teach you about in art in school? What about the three primary colors -- red, yellow and blue -- which cannot be derived by mixing any other colors, and the three secondary colors -- orange, green and violet -- which are derived by mixing the three primary colors? From which all other colors are supposedly derived from these "basic six?"

    Doesn't that suggest a sense of universality, as well as symmetry, in accord with the number six and a hexagram, where a hexagram (i.e., honeycomb effect) extends unto infinity?

  19. May 27, 2003 #18
    Alright, I'm glad to see that there have been some responses.

    I must say that I agree with Eh and Drag, that "color" [x=] "wavelength", but is rather a discription of the mental projection caused by the perception of wavelength in humans (obviously none of them used these exact words, I'm just re-stating in my own words).
  20. May 27, 2003 #19
    Re: Re: Re: The Advent of Color

    You're making a big error in perception.

    Colors are not mixed to make other colors. Instead two sets of matter which give off two different colors (in white light) are put closely together to give the effect of being one color. They are not making any new colors.

    "Mixing colors" is a perceptional illusion because of the size of pixels an eye can recieve.

    Stand back from a wall with small checkers and it can look like one color, get close and you see it is not.
  21. May 27, 2003 #20
    Iacchus32, regarding your question on universality:

    There is a certain disorder in some people where they see the complementary of every color. For expample, instead of blue they see orange and instead of green they see red. Wouldn't that mean that there is no universality in color perception?
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