Really good summary of the Color wheel and why it works

fjrabon · Dec 6, 2012

Color Wheels are wrong? How color vision actually works by @ASmartBear

This cleared up a lot of things I had always sort of dimly understood and wondered about color perception, physics of color and the color wheels (both reflected and projected).

TCampbell · Dec 6, 2012

So much of the beginning of the article was wrong that even if it was eventually correct later I couldn't make it through the story.

The three "primary" colors of "light" (aka the "additive" colors) are red, green, and blue. If LIGHTS emit red, green, and blue then you can combine them in combinations to make any other color. But that's because they are emitting their own light. This rule ONLY applies to "light".

The three "primary" colors on "paper" (aka the "subtractive" colors) are cyan, yellow, and magenta (those colors you see in your inkjet printer) and are NOT red, yellow, and blue (red, yellow, and blue are wrong and any texts that still use them are incorrect. This is because paper does not emit light. It reflects it. Since paper cannot generate light of it's own (not unless you set fire to it) all it can really do is alter the light that hits the paper. So assuming you shine "white" light on paper, the ink on the paper "subtracts" the wavelengths of light that it will reflect. That's why they are referred to as "subtractive" colors.

The article really goes down a rat hole when it gets to the physics. In physics color doesn't actually exist. Only wavelengths exist. The visible spectrum exists from roughly 400nm to 700nm. Oddly, our eyes have evolved to detect different wavelengths of light and represent them as different "colors" in the same way that our ears have evolved to detect different sound wavelengths and represent them as "pitches", but the "color" per se doesn't actually exist.

Color is created when the electrons orbit the nucleus of atoms jumps from one orbit (valance) to another. The distance it jumps determines the wavelength of the light and we assign a color value to this. Sorry to get so technical but the science geek in me goes nuts when I start to read a technical or scientific explanation which starts out by explaining myth as though it's fact. EVEN if the article eventually gets around to correcting the facts I sure do wish it would never have propagated more bad information.