🚀 go-pugleaf

Once upon a time, Mat Findlay (tetsuo@interlog.com) told this tale:
: "Charles Y. Kim" <aci02400@nuri.net> wrote:


: >Green is a combination of yellow and blue PAINT, not LIGHT... the three
: >primary LIGHT colors are red, blue, and green...

: Try again, hoss... Blue and yellow light, when combined, make green.
: Try putting a blue and yellow gel over a light sometime.


No, no, no!!!

red, blue, yellow (as in paints) is a subtractive color system.

red, blue, green (as in TV/Video monitors) is an additive color system.

In the above situation, putting a blue gel and a yellow gel over a light,
you're demonstrating the subtractive system.

If you want to demonstrate the additive system, take two lights, one with
a blue gel, and one with a green gel, and shine them on a white surface...

These are not the only possible systems. One other example is the CMY
(cyan, magenta, yellow) system used by printers. There are probably 
others besides that one.

Red, Blue and Yellow are the primary colors we're usually taught in grade
school because in grade school you're usually mixing paints or crayons which
is a subtractive color system. Red paint is red because it reflects mostly
red light, and absorbs other colors. Mixing blue paint with yellow paint
gives a mixture that absorbs all but green light. This is subtractive color
synthesis because each pigment you mix absorbs more light and makes the
result darker.


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	Kevin Morgan			|  Axiom of Infinity:
	San Jose, CA			!      An inductive (i.e. infinite)
	kmorgan@netcom.com  		|      set exists!

In the space of one hundred and seventy-six years the Mississippi has
shortened itself two hundred and forty-two miles.  Therefore ... in the
Old Silurian Period the Mississippi River was upward of one million
three hundred thousand miles long ... seven hundred and forty-two years
from now the Mississippi will be only a mile and three-quarters long.
... There is something fascinating about science.  One gets such
wholesome returns of conjecture out of such a trifling investment of
fact.
		-- Mark Twain