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CIE chromaticity diagram

Introduction to something called a CIE chromaticity diagram, it represents all colors humans can perceive.

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  • blobby green style avatar for user Megan Allen
    why is the triangle shaped like that
    (9 votes)
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  • stelly blue style avatar for user Aarya Baheti
    At it said CIE diagram, what does CIE stand for?
    (4 votes)
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  • duskpin ultimate style avatar for user Soulsphere
    I think he made a mistake when he says "this defines all colours of a single wavelength". Doesn't each colour have a different wavelength?
    (5 votes)
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    • leafers sapling style avatar for user Peter Collingridge
      Yes, each colour has a different wavelength. He means that the line around the outside defines the "pure" colours, those colours that can be produced by light of a single wavelength (such as pure red or pure green). The colours in the center of the diagram are colours that are produced by mixing the pure colours, so have a mixture of wavelengths. For example, white light cannot be produced with light of a single wavelength; you can only get it by mixing light with different wavelengths.
      (5 votes)
  • purple pi purple style avatar for user + - * / [L][A][T][H][A][N] \ * - +
    What happens if our eyes rest on something with a color we can't percieve? My guesses are it will be black, or look invisible.
    (2 votes)
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  • starky tree style avatar for user solas
    Why is there no dark green on the CIE diagram as there is on the color wheel?
    (4 votes)
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  • female robot grace style avatar for user STAR-PRO💖
    How do you make sure you get a properly colored movie in all forms and devices?? Can someone Heeeeeeelp Meee Pleeeeeaaaaase!
    (3 votes)
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  • duskpin ultimate style avatar for user ░▒▓█???█▓▒░
    what are cones and rods
    (3 votes)
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  • female robot ada style avatar for user Aaranya
    What is a CIE?
    (2 votes)
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  • blobby green style avatar for user Kashif Rizwan Khan
    Every now and then I keep stumbling upon articles stating that "human eye can perceive more shades of the colour green than any other". If that is true, why is do I see a larger area of the CIE diagram covered by blue-purple colours and not green?
    Or does it have something to do with my screen's colour gamut?
    (2 votes)
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  • starky sapling style avatar for user .𝕄ochita.
    Why do printers have ink colors Black,Cyan,Magenta & Yellow and why not Blue,Green and Red?
    (1 vote)
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    • female robot grace style avatar for user STAR-PRO💖
      In elementary school we are taught that Red, Yellow, and Blue are the primary colors, so then why do printers use CMYK (Cyan, Magenta, Yellow, and Black)? And why do TV’s and monitors use Red, Green, and Blue? The answer is actually pretty straight forward and easily explained.The first thing to understand about colors is the difference between being additive and subtractive. This will help us understand why monitors use RGB and printers us CMYK.Why Do Printers Use CMYK-14

      To put it simply, on a monitor, light is being emitted (or added), which is important because when you emit (or add) Red, Green, and Blue they create White.R+G+B = White (light)
      When we look at ink or paint however, light is being absorbed (or subtracted) and when you absorb Red, Green, and Blue you get Black R-G-B = Black (Ink)
      This is the foundation for understanding why printers use CMYK, while we normally see TVs and computer monitors using RGB.
      *CREDITS FOR THIS INFORMATION GO TO THE RIGHTFUL AUTHORS*
      (2 votes)

Video transcript

(springing) (thudding) - Now let's return to the human eye for a moment. Remember, the human eye is the sensor which light must pass through to be perceived. So we need to understand the limit of the human visual system. In the 1920s, experiments were done to map the color space perceivable by humans. From purple, all the way around the rainbow, to this red, this defines all colors of a single wavelength. These are known as spectral colors, and inside this region, we have all combinations of those pure colors. Scientists plotted the limit of the pure colors we can perceive. Notice it takes this funny looking shape. One reason this shape is useful is something called perceptual uniformity. That's a fancy way of saying that we can find the mixture of two colors, such as this red and this green, by simply looking at the midpoint of them, right here. It's known as the CIE chromaticity diagram. CIE refers to the scientific group that published the findings. Compare this to the hue saturation color wheel, which is not perceptually uniform. Pure red is here, pure green is here, but the middle of these two points is not pure yellow at all, it's a very desaturated yellow. Okay, let's pause here. In this next exercise, we'll challenge you to think more about this CIE chromaticity diagram, and perceptual uniformity.