Why does mixing red, yellow, & blue paint yield black?

If white light is all the primary colors, why does mixing red, yellow, and blue paint yield black? I know the answer is probably simple, but I don’t know what it is.

I believe it yields brown.

I’ve done it with watercolors and got the blackest black I’ve ever seen.

You are confusing primary colors of light with primary colors of pigment. When dealing with pigments, color mixing is subtractive. This is because pigments absorb the white light that hits them and reflect back certain ranges of wavelengths, giving them color. The subtractive primary colors are yellow, magenta and cyan. When you mix them together, they absorb everything and reflect nothing, yielding black.

When dealing with things that create light, such as a television, you have additive color. Additive color mixing occurs when two sources of light emit light with differing wavelengths. The two sources of light blend together, creating a new color. The primary additive colors are red, green and blue. Mixing them all gets you white light.

Great! That does it. Mod, you can lock it up, I suppose.

By the way, you usually don’t get a good, solid black when you mix magenta, yellow, and blue. That’s why the offset process use CMYK, with k standing for black.

What’s an offset process?

He means a process of transfering ink to paper, which is probably irrelevant for the purposes of this discussion. “Offset” means that there’s an intermediate step between the original and the duplicate. Ink is transfered from a metal original to a rubber (intermediate) roller, and then on to the paper.

A color inkjet printer uses direct transfer, but will usually have 4 inks. Cyan, Magenta, Yellow and Black.

He means a process of transfering ink to paper, which is probably irrelevant for the purposes of this discussion. “Offset” means that there’s an intermediate step between the original and the duplicate. Ink is transfered from a metal original to a rubber (intermediate) roller, and then on to the paper.

A color inkjet printer uses direct transfer, but will usually have 4 inks. Cyan, Magenta, Yellow and Black.