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Red, green, blue light on three-sided rotatable pyramid.

• E+5+5

diagram for demo

Red, green, blue light on three-sided rotatable pyramid. The pyramid base is 12 inches on a side. The pyramid can be rotated so that pairs of colors can be summed on each of its surfaces, or the individual colors can be represented. The pyramid is shown here in the position which sums pairs of colors.

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E+5+0 Standard color blindness tests and box of colored yarns. E+5+10 Newton's color disk: When rotated,appears white. E+5+15 Three-color projector for additive color mixing with arc lamp. E+5+20 Arc light spectrum recombined with concave mirror on lucite rod. E+5+25 Cyan, magenta, and yellow filters mix subtractively on OHP. E+5+30 Arc light spectrum with various filters. E+5+35 Rotating disk with black and white lines makes color illusion. E+5+40 Purkinje effect: At low intensity, blue is more visible than red. E+5+45 Two slides plus red and green light gives full color illusion. E+5+50 Applet: Color Vision E+5+55 Applet: Optical Illusions E+5+60 Applet: Additive Color
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