The Properties Of Color; The Physics Of Color - Minolta Color PAGEPRO EX Manual

The Properties of Color

The Properties of Color
What we call "color" is really a perceptual ability unique to humans
and a small number of animal species. Color theory is an attempt to
systematize the properties of color perception, which by nature is
relative and changeable. A color appears different depending on the
other colors around it, and individuals vary in their abilities to
perceive color.

The physics of color

The human eye can see electromagnetic radiation at wavelengths
between 400 nanometers (purplish blue) and 700 nanometers (red).
This range is called the visible spectrum of light. We see pure
as intensely saturated or pure colors. Sunlight at
spectral light
midday, which we perceive as white or neutral light, is composed of
light from across the visible spectrum in more or less equal
proportions. Shining sunlight through a prism separates it into its
spectral components, resulting in the familiar rainbow of colors.
Like the sun, most light sources we encounter in our daily
environment emit a mixture of many light wavelengths, although the
particular distribution of wavelengths can vary considerably. Light
from a tungsten light bulb, for example, contains much less blue light
than sunlight. Tungsten light appears white to the human eye which,
up to a point, can adjust to the different light sources. However, color
objects appear different under tungsten light than they do under
sunlight because of the different spectral makeup of the two light
sources.
The mixture of light wavelengths emitted by a light source is reflected
selectively by different objects. Different mixtures of reflected light
appear as different colors. Some of these mixtures appear as relatively
saturated colors, but most appear to us as grays or impure hues of a
color.
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