How come if you mix red blue and yellow light you will get white light but when you mix red blue and yellow paint you get brown?

Answer 1

Red, yellow and blue paints are called subtractive primary colors, because they work by absorbing most of the light which strikes them except at their actual color. For example, if white light strikes blue paint, all of the colors except blue are largely absorbed while the blue component of the white light is reflected, giving the paint its perceived color.

If we take paint which absorbs everything except blue and mix it with paints which absorb everything except red and yellow, all that will be left will be light which looks brown.

Mixing light -- the additive primary colors -- works the opposite, with each of the primary colors filling in a portion of white light which is missing from the others.

gafisher

The first part of the question doesn't address substrative color mixing. If mixing yellow, red, and blue light produces white light, then red, yellow, blue mixing = red, blue, green mixing. Substrative brown? I think all senses of color is a function of the nature of consciousness, in that color vision frequencies affects consciousness, which creates the sense of color; not only color, but all the other qualia of the senses we have...sound, touch, taste, smell, etc. The qualia (experiences that cannot be explained by energy forms and its wavelengths alone) of our senses provide clues about the nature of consciousness.

D. Sprague

Answer 2

When you mix red, blue, and yellow light, you get white because they are additive primary colors that combine to create white light. In contrast, when you mix red, blue, and yellow paint, you get brown because they are subtractive primary colors that absorb light and reflect a different color wavelength, resulting in brown when mixed together.