Transmitted Light

A transmissive object allows light to pass through it and may absorb a section of the spectrum.
The color of the object in this case will depend on the wavelengths of light that are allowed to
pass through.

Emitted Light

An emissive object emits light. The appearance of the light will depend on the wavelengths
emitted.
Color Registration
The CMYK printing process uses overlapping toner of cyan, magenta and yellow. To produce
the best possible output, the colors must print in specific positions so that overlaps and dithering
are accurate. If the colors are not aligned, the resulting print will have color shifts (colors
produced where incorrect colors overlay to produce an undesired color) or appear blurred.
Using black to print gray tints and black text eliminates the problem when printing gray and
black, but not when color is constructed from two or more of the process primaries.
The illustration shows how registration problems can cause undesired affects.
Color Wheel
The relationship between colors can be best shown on what is known as a color wheel. The hue
value of a particular color is expressed in degrees. For example, the additive primaries are
displaced by 120° from each other: red at 0°, green at 120° and blue at 240°. The subtractive
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