What Colour is an Orange in the Dark:

Discussion in 'General Science & Technology' started by paddoboy, Sep 17, 2015.

  1. sideshowbob Sorry, wrong number. Valued Senior Member

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    I've seen that too. Amazing!
     
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  3. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Even more amazing is that after a couple of weeks of constant wearing of "inverting glasses" at least one man could ride his bike thru traffic. When he took them off, it only took a few days for him to be able to walk well again. While wearing the glasses, he had retinal images right side up, not inverted as we all do.
     
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  5. sideshowbob Sorry, wrong number. Valued Senior Member

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    Does that mean he saw things upside-down? Or did his brain re-invert them?
     
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  7. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Initially yes. All vision was inverted. - the first few days with glasses on, it was very difficult to do ordinary things, like walk and eat - better done with eyes shut, but in two weeks or so even riding a bike in traffic was not very hard. When the inverting glassses were removed, the recovery to normal functioning with retinal images inverted was much faster and easier.
     
    Last edited: Oct 17, 2015
  8. Waiter_2001 Registered Senior Member

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    ...black is not a colour...
     
  9. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Not normally considered to be, but in V5, where color information is extracted there are three "orthogonal" color axises:
    Red/green, Yellow/blue & Grey scale or white/black axis.
     
  10. Write4U Valued Senior Member

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    Black is the absence of light. No light, no color.
     
  11. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Again, that is the conventional POV, but if one looks at what is happening in V5, the primary color processing /identifying part of the brain, it is like almost all other areas. The null condition does not mean no neural activity but balanced activity.

    You can distrub the balance that normally has you experience "white" in the red/green axis by staring at an intense red spot for a few minutes. Then when looking a white wall illumisted by white light you see same shaped spot in green color. - The "over-worked" red end of the axis nerves have been fatigued and under white light stimulation can not blance out the activity in the green end of the red/green axis.

    Just bcause there is no light, does not mean there is no neural activity in the three orthogonal color axises. In general it is the CHANGE in back ground activity that is the perceptual effect.
     
  12. Write4U Valued Senior Member

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    I agree.
    I disagree on that point. IMO, in the absence of light waves(emitted or reflected) there is no perceptual effect, which depends on the sensory observation.
     
    Last edited: Oct 30, 2015
  13. paddoboy Valued Senior Member

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    I'm also of that opinion. Black is not a colour...Black is the absence of colour.
     
  14. Write4U Valued Senior Member

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    What always intrigued me is that the combination of primary colors in light, produce white light, but when we mix primary colors of paint, the result is black. (due to the absorption of all light waves.)
     
  15. gmilam Valued Senior Member

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  16. Write4U Valued Senior Member

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    Is the second set not called the set of "complementary colors?

    https://en.wikipedia.org/wiki/Additive_color
    https://en.wikipedia.org/wiki/Subtractive_color[/QUOTE]
    Yes, I based my post on these phenomena. Thanks for the links, which I forgot to include.

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    Additive color mixing: adding red to green yields yellow; adding all three primary colors together yields white.


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    Subtractive color mixing.

    The intriguing part is that both primary sets show up in each example, but in a kind of reverse order and from mixing different primary and complimentary colors, which seems counter-intuitive at first, but observably true.
    I don't think this negates the proposition that the absence of all light leaves can only produce
    black)

    Can these phenomena, (additive) R + G + B = White, and (subtractive) M + C + Y = Black, be quantified by mathematical equations?

    My reason for asking is that it might be related to another thread currently in progress.
     
    Last edited: Oct 30, 2015
  17. Write4U Valued Senior Member

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    As can be clearly demonstrated with several optical illusions such as this:
    http://www.huffingtonpost.com/2013/05/23/10-optical-illusions-that-will-blow-your-mind_n_3307500.html
    Look for the black and white apartment illusion, and the circling pink dots illusion.


    I agree, but with the qualification that your example is not addressing the OP, because it presupposes a previous experience of seeing an orange as being orange in color. Thus that information is already recorded in the brain and can be recalled (imagined) even in the absence of light.

    But if I am blind and have touched and smelled an orange, it really makes no difference if I am in a dark room or in full daylight. I would be able to recall the shape and fragrance from memory, but I would not be able to mentally visualize its color, becasue I have never seen any color at all and my neural network has no way of recalling the color. I have no mental reference to any color, although I might experience flashes of neural trauma. But that has nothing to do with sight itself.

    I am no expert, but as sight is our main sensory ability, it interests me.
     
  18. Waiter_2001 Registered Senior Member

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    Observation of the spectrum of colours fails to yield black: it is therefore not a colour. As has been established black is simply the absence of colour.

    However my question is this: what must I DO to distinguish between the absence of LIGHT and the absence of COLOUR?
     
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Light is objective - measurable but color is subjective and depends upon the type of creature perceiving it. For example, all the flowers that are "white" to you have many different colors to the honey bee whose eyes sense the UV part of the spectrum. That is how it goes unerroringly to the flower that currently is flowing with nectar among many others that are all white to you.

    Some people lack one of the three wave lenght selective retinal sensors - their colors are not the same as yours. You can distinguish two as different which they see as identical. Color is a subjective experience in the beholder, not objective as EM radiation is.
     
  20. Write4U Valued Senior Member

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    Perhaps Black does not generate an EM wavelength?

    The observation of EM wavelengths.

    I believe it is assumed that since the BB the "Pilot Wave" of the universe has a current wave frequency of 13 occillations in 13.7 billion years. A pretty long wavelength. The expansion of the universe seems to be accelarating, but perhaps we are reaching the peak and will relatively soon begin to shrink as part of the wave function, each time taking a little longer, until the frequency rate has completely flattened and we have reached the exaustion of universal energy. What will happen to the semi-autonomous dynamic systems (such as our galaxy or even our dolar sustem) during these times of expansion and contraction can only be theoretically approximated. The maths (of potential implications) are overwhelmingly large.
     
  21. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    So you do not dream in color, like most do. Color is a subjective experience and not always dependent upon visible EM radiation entering the eye.
     
  22. Write4U Valued Senior Member

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    Color is a subjective experience for "sighted" people who have experienced EM radiation and processed it as color.
    But if your brain has never experienced color, how could you possibly imagine a color. As I said, perhaps a blind person may experience "flashes", such seeing "stars" when we bump our heads, but that would be result of trauma to the internal neural network and not connected to the visual circuit at all.
     
  23. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I agree with this. I believe in subjective "qualia" as I have experince many of them. Some do not. This is a classic philosophical discussion
    Thomas Nagel agreed:
    And I agree with Nagel. Qualia is what no artificial intelligence machine will ever have.
     
    Last edited: Oct 30, 2015
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