Originally Posted by dmatson
I thought white was the absence of color and black was the combination of all colors. I did sleep at a Holiday Inn
I can't believe I got to this before David Shealey.
Depending on how you define it, black is the absence of all color OR
the presence of all color.
An object has a given color because it absorbs part of the light that hits it while reflecting the rest of the visible spectrum. The wavelengths that are reflected to the eye are what give the object its color.
For example, a pigment that reflects energy mostly in the 440-490 nm wavelength is considered blue
If you mix enough pigments together, they all gobble up any bits of the spectrum that any one pigment would have reflected. Little to none of the spectrum bounces back to the eye, and the object appears black.
Adding paints, dyes, and colorants uses this "subtractive" color model, where each color filters out a bit of the (presumably) white light that bounces back to the viewer. In the subtractive model, yellow combined with blue (cyan) gets you green.
On the other hand, the monitor you're looking at right now is using an "additive" model, where energy is not reflected, but rather emitted, in specific wavelengths. Here, green combined with yellow gets you red.
Thus, if you combine all the colors on your monitor at 100%, you'll get white. Whereas, if you combine all the colors in a color copier, you'll get black.
Which, of course, is the fastest