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Introduction to Gamuts

Gamuts represents the range of colors any given device can produce. They are represented as a region within the CIE chromaticity diagram.

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  • aqualine ultimate style avatar for user Emma
    If no device can produce pure red, green and blue; then how does the full color of the CIE diagram show the complete range on the video in the lessons? Are the images in the videos above made differently than movie scenes?
    (15 votes)
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  • orange juice squid orange style avatar for user Urvi
    The CIE diagram represents the complete perceivable colour space for the human eye, and the image of the diagram that I see is being displayed by my monitor, which should have it's own smaller gamut. Obviously, the monitor will have its limitations in reproducing certain colours.
    So does it not make sense to say that what is being shown in the video via the monitor is not really the absolute complete perceivable colour space for the eye?
    Is it possible to create a representation(maybe not digital) of the true colour space?
    (3 votes)
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  • leafers seedling style avatar for user Kean Goodwin
    Around 57 seconds. If no monitors can produce pure colors, why do I see them in the video?
    (4 votes)
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  • leafers tree style avatar for user EmeraldAnimus
    At , the colors show different on each device, but how than are we able to see the color differences AND the pure colors on the diagram?
    (3 votes)
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  • leafers ultimate style avatar for user Aidan Smith
    If monitors can only produce those colors in the gamut then how come my computer is able to display the colors outside of the gamut?
    (3 votes)
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  • blobby green style avatar for user Nomari
    The sun is bigger than the moon.The moon didn't blocked the moon.It looks that way because the moon and the sun are 150 kilometers away from eachother. The moon is far enough to look like it is blocking the sun when it very is orbiting around the sun.
    (2 votes)
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  • primosaur ultimate style avatar for user emma johnston
    wait if technology devices can only produce the colors inside the gamut but i'm watching this on a computer...
    (2 votes)
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  • duskpin sapling style avatar for user Ruqayya Ismail
    also how can u get pure red green blue color?(the last question i ment um color insted of light:)
    (1 vote)
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  • duskpin sapling style avatar for user Ruqayya Ismail
    could u combine the projecters light with the monators light to get the right color?and if u could how?
    (1 vote)
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  • duskpin ultimate style avatar for user ░▒▓█???█▓▒░
    why are red green and blue not pure?
    (1 vote)
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Video transcript

- Okay, so let's step back to the larger problem. Our finished movies are viewed in a number of different ways. For instance, the screen a movie is displayed on could be a monitor, like this, or a projector, like this, and that's where another problem creeps up. Both of these displays are getting the same color signal of pure red. Notice these resulting colors we see aren't exactly the same. The problem is display devices, like monitors and projectors, can only reproduce some of the perceivable colors. It's the pure, or single wavelength, red, green and blue light, they have trouble creating. Notice, this screen can generate a slightly purer, or deeper, red compared to this one. Remember, on our CIE diagram that the purest red, green, and blue are way out on the edge, here, here, and here. But, a typical RGB monitor can't create anything close to pure red, green, and blue light. If it tries to display those colors, the best it can do is hit three points over here, here, and here. And, since the display can blend those colors, the device has the ability to create any colors in this black triangle. This region is called the Gamut of the display device. It's the range of the perceivable colors any give device can reproduce. Mathematicians would say the Gamut is a subset of the perceivable color space. The size of this set is important to filmmakers because they want the biggest palate of colors to paint from. More color means more artistic freedom. For a long time, our movies were projected on film which has a very large Gamut, like this. Eventually, we moved to digital projectors which had a different Gamut compared to film. More recently, laser illuminated digital projectors have been introduced which have a much larger Gamut than film. This is because they use laser light which is very close to a single wavelength allowing them to produce very pure reds, greens, and blues. But here's a practical problem for you to think about. How do we make sure our movies look good on any device, especially if they have very different Gamuts? You can think about that while working on the next exercise.