Good question, and it has to do with why violet and purple are different things. We have receptors in our eyes for long wavelengths (red), middle wavelengths (green), and short wavelengths (blue). Violet has a shorter wavelength than blue, but we don’t see it as just another shade of blue because our red receptors also have a little bit of response in the very short violet wavelengths. This is also the reason why we see purple as looking similar to violet – it also triggers both red and blue receptors, only purple does it by actually emitting/reflecting some of each. So violet = shorter wavelengths than blue, purple = some red and some blue, those are quite different, and our eyes see them similarly.
This is similar with magenta and how (as anyone with a color printer will tell you) if you mix yellow and magenta together, you get red. And when looking trough a camera that can see infra red wavelengths, it looks like it’s the color magenta. Looking at the light spectrum, half way between yellow and infra red is red.
If you want a color that definitely doesn’t exist, go with magenta. Purple is too often (as seen in other comments) taken to be a synonym for violet (400-410 nm light).
(That said, our eyes don’t have receptors for violet, which merely triggers our blue receptors but with less triggering of green and red than blue has…so our brains see violet as super blue, just as we see real yellow light as equal strengths of red and green.)
You’re equating not being able to see the color with it not existing. Violet exists because the wave length exists. There is no wavelength for a blend of red and blue as halfway between their wavelengths is where the green wavelength exists.
Exactly. Purple doesn’t exist as a “pure color” (defined as a color we perceive that’s produced by a single wavelength of light). A laser can only generate a pure color – you can’t make a laser that’s purple (or brown, or pink, or gray, or white). You can make a violet laser, though (I have a violet laser pointer).
You can blend nearby colors like red and green to get what your eyes recognize as yellow (if you’re blending light, that is – blending pigments would be a different matter; that’s additive vs. subtractive color, which is another matter entirely). But that only looks like pure yellow because pure yellow is within the response range of both your red and green color receptors – it triggers them both, just as a mixture of red and green light does. But as you say, in general that doesn’t work – blending two colors and averaging their wavelengths are two different things.
stating ‘wavelength’ is rather pointless, as most of us have three receptors, and some lucky people have sensitivity into UV..
search ‘Some Of You Can See The Invisible’ on ytube – lots of info the comments!! 🙂
You’re missing the point. It doesn’t matter what one can perceive, or what cones or rods the eye has. We’re only talking about wavelengths. Specifically that “purple” doesn’t exist where our brain tells us it should. Going by wavelengths, halfway between red and blue gets us green. That’s it. That’s the point. Don’t overanalyze this.
Hold on… that only applies to HUMAN vision and sensibilities. Even in the animal kingdom there are animals with more and less photo receptors than we have. The way she perceives color may be entirely different from humans thanks to her other half and she may in fact be able to see purple as an actual color independent of blue and red.
See the links in Paul’s replies above.
Many colours don’t exist anywhere in the EM spectrum, but instead exist as combinations of several non-overlapping sections of it.
In purple’s case, a red section and a blue section.
In fact, if you examine this web page very carefully, and exclude users’ avatars, the only colour that exists in the EM spectrum that is actually present is the red in the unfollowed links.
That’s not the point of what is being said. If you go halfway between and of the wave frequencies, you will get a wave frequency for the mix of those two colors. But half way between red and blue, you get green. That’s the point being made.
If you want to go even further down the rabbit hole, there is no such thing as color outside of your head. Light and color are just your brains interpretation of solar radiation and not an inherent property that exists anywhere but inside your brain.
We all live in a pitch black silent universe and our brains just create a holodeck illusion of whatever radiations and vibrations come in contact with our bodies.
There’s even a philosophical question as to whether the way one persons brain interprets what it perceives is the same as the way another’s does.
Even in typical human color vision, with three typical color receptors (of substantially overlapping sensitivities), color perception is the result of a red/green, blue/yellow antagonistic system rather than a direct mix of red/green/blue. The Lab (or Lab*) color system is an attempt to capture those red/green and blue/yellow values as explicit coordinates. (And that’s not even touching on the strong impact of context on color perception, or even value (lightness) perception.)
So, yeah, there is no wavelength for purple. Doesn’t stop humans from perceiving a multimodal frequency distribution as purple. So it makes sense to say that multimodal distribution _is_ purple, just as some single wavelength is spectral red.
What about violet?
Wrong comic. She’s in the Incredibles. 😉
https://grantsonnex.com/why-purple-doesnt-exist/
And here my folks were always telling me I’d never learn anything from reading the funny pages… 🙂
Same deal with the browns, only slightly more complicated.
Good question, and it has to do with why violet and purple are different things. We have receptors in our eyes for long wavelengths (red), middle wavelengths (green), and short wavelengths (blue). Violet has a shorter wavelength than blue, but we don’t see it as just another shade of blue because our red receptors also have a little bit of response in the very short violet wavelengths. This is also the reason why we see purple as looking similar to violet – it also triggers both red and blue receptors, only purple does it by actually emitting/reflecting some of each. So violet = shorter wavelengths than blue, purple = some red and some blue, those are quite different, and our eyes see them similarly.
This is similar with magenta and how (as anyone with a color printer will tell you) if you mix yellow and magenta together, you get red. And when looking trough a camera that can see infra red wavelengths, it looks like it’s the color magenta. Looking at the light spectrum, half way between yellow and infra red is red.
Last frame: Castela looks like she going to just lift her head from her shoulders and toss it in a waste basket.
This might explain why my color senses are different from others. I was always thinking it was just my autism and related to my dyslexia
yes.
If purple is unnatural, does that mean all the flowers we think of as purple are actually violet?
Or they just has bits of blue and red close together. This explains the tech stuff: https://www.zmescience.com/feature-post/natural-sciences/physics-articles/matter-and-energy/color-purple-non-spectral-feature/
“Green exists where ARE brain tells us purple should be.”
If you want a color that definitely doesn’t exist, go with magenta. Purple is too often (as seen in other comments) taken to be a synonym for violet (400-410 nm light).
(That said, our eyes don’t have receptors for violet, which merely triggers our blue receptors but with less triggering of green and red than blue has…so our brains see violet as super blue, just as we see real yellow light as equal strengths of red and green.)
You’re equating not being able to see the color with it not existing. Violet exists because the wave length exists. There is no wavelength for a blend of red and blue as halfway between their wavelengths is where the green wavelength exists.
Exactly. Purple doesn’t exist as a “pure color” (defined as a color we perceive that’s produced by a single wavelength of light). A laser can only generate a pure color – you can’t make a laser that’s purple (or brown, or pink, or gray, or white). You can make a violet laser, though (I have a violet laser pointer).
You can blend nearby colors like red and green to get what your eyes recognize as yellow (if you’re blending light, that is – blending pigments would be a different matter; that’s additive vs. subtractive color, which is another matter entirely). But that only looks like pure yellow because pure yellow is within the response range of both your red and green color receptors – it triggers them both, just as a mixture of red and green light does. But as you say, in general that doesn’t work – blending two colors and averaging their wavelengths are two different things.
stating ‘wavelength’ is rather pointless, as most of us have three receptors, and some lucky people have sensitivity into UV..
search ‘Some Of You Can See The Invisible’ on ytube – lots of info the comments!! 🙂
also look at https://midimagic.sgc-hosting.com/defvison.htm
this shows that many have receptors sensitive to more than just one wavelength..
You’re missing the point. It doesn’t matter what one can perceive, or what cones or rods the eye has. We’re only talking about wavelengths. Specifically that “purple” doesn’t exist where our brain tells us it should. Going by wavelengths, halfway between red and blue gets us green. That’s it. That’s the point. Don’t overanalyze this.
but by the same metric. yellow does not exist…
https://www.youtube.com/watch?v=R3unPcJDbCc
there is no red in this, but your brain says there is!!!! :O
https://www.youtube.com/watch?v=MJBfn07gZ30
Hold on… that only applies to HUMAN vision and sensibilities. Even in the animal kingdom there are animals with more and less photo receptors than we have. The way she perceives color may be entirely different from humans thanks to her other half and she may in fact be able to see purple as an actual color independent of blue and red.
See the links in Paul’s replies above.
Many colours don’t exist anywhere in the EM spectrum, but instead exist as combinations of several non-overlapping sections of it.
In purple’s case, a red section and a blue section.
In fact, if you examine this web page very carefully, and exclude users’ avatars, the only colour that exists in the EM spectrum that is actually present is the red in the unfollowed links.
It still doesn’t change that the wavelength for purple (half red, half blue) doesn’t exist as purple but green.
that is two wavelengths – 575mm for red, 445mm for blue..
on the ‘Subtractive color model’ (using water colors) mix blue and red to make purple..
only trouble is, some paints are not that perfect.. try this link sfor more!
https://paintinggal.com/what-colors-make-violet-the-color-mixing-guide-included/
but for most color displayed using light you need ‘additive color mixing’ good link including web codes for your page!! 🙂
https://www.hoodmwr.com/what-color-red-blue-make-mixed/
Castela is a plant. She might feel EM radiation instead of seeing it.
Tina sees (or at least used to see) that way.
We can feel EM radiation, as well as see it, too.
Cass’ senses probably feel it to a greater extent than we do.
Purple isn’t a colour, purple is a fruit.
Somebody hit Cass’ reset button. Processing appears to have hung.
I like purple…
It’s the taste of accidentally time travelling via a microwave oven.
Yum.
“Non-spectral colors” ARE STILL REAL COLORS, is the thing.
(Also, “violet” is one, and the difference between “violet” and “purple” is at BEST unclear.)
That’s like saying “brown isn’t a color because a prism doesn’t emit brown in the rainbow”; the problem is color is not limited to spectral colors.
Brown is a color. Purple is a color. Pink is a color.
Neither optics nor artistry nor biology support “only spectral colors are ‘real'”.
That’s not the point of what is being said. If you go halfway between and of the wave frequencies, you will get a wave frequency for the mix of those two colors. But half way between red and blue, you get green. That’s the point being made.
If you want to go even further down the rabbit hole, there is no such thing as color outside of your head. Light and color are just your brains interpretation of solar radiation and not an inherent property that exists anywhere but inside your brain.
We all live in a pitch black silent universe and our brains just create a holodeck illusion of whatever radiations and vibrations come in contact with our bodies.
There’s even a philosophical question as to whether the way one persons brain interprets what it perceives is the same as the way another’s does.
All of this! ^_^
Very true. Color is a perceived experience. Even some humans provably don’t perceive the same colors that others do.
Even in typical human color vision, with three typical color receptors (of substantially overlapping sensitivities), color perception is the result of a red/green, blue/yellow antagonistic system rather than a direct mix of red/green/blue. The Lab (or Lab*) color system is an attempt to capture those red/green and blue/yellow values as explicit coordinates. (And that’s not even touching on the strong impact of context on color perception, or even value (lightness) perception.)
So, yeah, there is no wavelength for purple. Doesn’t stop humans from perceiving a multimodal frequency distribution as purple. So it makes sense to say that multimodal distribution _is_ purple, just as some single wavelength is spectral red.
Did Stela’s brain get fried because Briar called her ‘thoughtful and kind’? Or because she just learnt a colour only exists because we think it does?
Briar is DEFINITELY one for the books…