Comments by "EebstertheGreat" (@EebstertheGreat) on "Why no two people see the same rainbow" video.

@ScienceSpider-sigma You are confusing violet with purple. Violet is the highest-frequency part of the visible spectrum. Purple is a mixture of violet and red light. If you mix blue and red, you will get a color close to the line of purples, i.e. a slightly less saturated purple such as magenta. But it won't be violet. The fact that violet closely resembles purple to the human eye is a result of how the visual signals are processed by the optic nerve and brain. They aren't actually the same thing.
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@sathivv950 Yeah, it's easy to see the difference if you look at paint swatches or flowers, but it's much harder when looking at a screen, since they just have to do their best to approximate violet with a bluish purple. It's hard to see the difference between purple and purple lol. To me, "ultrablue" reminds me of "ultramarine," the deep blue pigment in lapis lazuli. And that can indeed have a violet tinge, though typically it is just blue. Also, it's worth pointing out that in addition to spectral violet (the wavelength of light), the term "violet" is also used in various color wheels, including RGB and RYB, where it necessarily has a different meaning (and is a kind of purple).
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@chlojolo I wasn't suggesting a "special term." I was making fun of "ultrablue." And technically, no screen can produce a purely monochromatic color, but LED screens come pretty close. Actually, a violet LED should in principle be able to look more saturated than any blue or green LED, since its output can overlap the edge of the visual spectrum.
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@ScienceSpider-sigma No. That is not violet. That is blue. You can't make violet out of red, green, and blue, because violet is a spectral color that is not red, green, or blue. You can't make any spectral colors out of primaries, not even spectral yellow or cyan.
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@ScienceSpider-sigma That is a projection of violet onto the sRGB color space, where it ends up as a purple. All colors have to be squished down to your monitor's gamut, because those are the only colors it can display. But get some Pantone color swatches and compare them to what even the best monitor can output. You will find many colors that the screen cannot replicate exactly. Spectral violet is rare in nature, even rarer than blue. Our eyes also don't respond much to it, so it looks very dim, making it hard to pick out in rainbows and such. Spectral colors in general are extremely rare in nature, as almost everything you see is a mixture of various frequencies of light, but violet is even hard to create cheaply. One way to see true violet light is to buy a blacklight. Although most of the light emitted by the blacklight is ultraviolet, some of it is violet, and that is the visible light you see. It's still not totally saturated, but it is a very high quality violet. Don't get your hopes up too much though. It will still look purple, because violet looks pretty purple to the human eye. However, it will be a purple you cannot recreate on your RGB screen.
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