All colour is perception created by the brain. The eyes provide raw data. If you are perceiving something you want to call magenta, then go ahead and call it a colour.
Color theory is a lot more complex then that.
Magenta is a color, in fact it is one of the primary colors of subtractive color theory.
It depends if you are discussing additive (light) or subtractive (pigment) color theory.
Additive color theory focuses on the light, and the light the eye perceives are Red Green and Blue photons, which is why TVâs and other light projectors mix RGB. All colors can be made from mixing Red Blue and Green light.
Subtractive color theory focuses on the âcolorâ of the object itself which is what determines what is absorbed and what is reflected. In pigments all colors can be made from mixing Cyan Yellow and Magenta pigments (CMY). This is why inkjet printers can make all the colors using Cyan Yellow and Magenta ink cartridges. They often include a Black cartridge as well to get a âtrue blackâ (K) and save the others from the excess of black printing associated with text (CMYK)
You cannot make all colors by mixing CMY light, nor can you make all colors by mixing RGB pigments.
Color theory is something incredibly fascinating to study, and people who havenât studied it thoroughly tend to get hung up on one side or the other and argue the that opposite is incorrect, when really they are inseparable.
âA ship loaded with red paint ran into a ship loaded with purple paint this afternoon. At last report, both crews were still marooned.â
My first response to this was âWait, it doesnât? I thought violet and indigo were official ârainbowâ colours?â
Then I watched the video, and it was pretty much this:
I have a friend who insists that the atmosphere isnât blue, because [explanation reduced to noise through having heard it so many times, but the words âRayleigh scatteringâ are in there somewhere] and so the colour isnât produced in the regular way. The sky is blue, but the air isnât. What happens if you take the air away and replace it with, say, chlorine, I ask? The sky becomes green, he says, because chlorine is green. But oxygen-nitrogen isnât blue, I say? Werenât you listening, he asks? Then he goes into the explanation again.
So tell me again how magenta isnât a colour, despite the fact that I can point to it in RGB, HSL, CMYK and Pantone. I need to zone out for a bit while I do some photoshopping.
Thanks!
I came here to say: âif magenta isnât a colour, then yellow and cyan arenât colours either.â
/I work with this stuff all day long.
Except there totally is a purple section of rainbows, right? Definitely not magenta, but a nice deep purple/violet after the blue. So what is getting added or removed at that point, as the wavelength moves out of the visible spectrum?
ââŚand maybe some unnamed creature
stayed awake all night in the
midst of a thousand miles of colour
just to see what it felt like
to have all the blue-purple there was
explode in his brain
and alter both present and futureâŚâ
From Al Purdyâs In the Early Cretaceous
Heâs not even wrong. The color we call âvioletâ from the rainbow does exactly the same thing that he says âmagentaâ does. It stimulates the red and blue cone cells in your retina, but not the green cone cells. Even though itâs not âin betweenâ blue and red. Youâll also note that the pure frequency of âvioletâ in the rainbow does not contain any green wavelengths. Thus the lack of green in it. Just like âmagenta.â
Such as the guy who very earnestly tried to convince me that clearly laser printers must print in RGB because lasers are just light, right?
Is it just me who wants to know - Where do you get hold of the colored torches?
So the red cones respond to wavelengths around the color red and to wavelengths shorter than blue?
It is a colour. Itâs just not a spectral colour.
(And your âredâ, âgreenâ and âblueâ cones are actually most sensitive to orange-yellow, yellow-green, and blue-violet. But using red, green and blue in TVs and computer displays gives a better spread of colours.)
It just might be the language that is inadequate and not the physical world.
But thatâs not quite the same thing, is it? Because you can point to a wavelength (indeed, many wavelengths) and say âthis is yellow lightâ, and similarly for cyan; but thereâs no wavelength you can point to and say âthis is magenta lightâ.
Yes, red and blue cones both fire when you look at violet rainbow light. Even though the wavelength is shorter than blue, the red cones do actually fire. They are not limited to only firing on the longer red wavelength.
Not really. Youâre arguing semantics. There is a wavelength of light that produces the sensation of yellow. There is no wavelength of light that produces the sensation of magenta - you can only do it by mixing two different wavelengths. (You can also produce a sensation of yellow by mixing two different wavelengths, but this will only work if the viewer is a trichromat, which most of us are)
When he says âcolorâ he means something like âa pure wavelength of visible lightâ, when you say color, youâre talking about something like the specific sensations we get. Youâre just talking past each other.
There is indeed a spectral color that stmulates blue and red cones. We use the word âvioletâ for it.
Violet is not magenta. The mechanism is similar, but the values are not.
