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Color is a Phenomenon
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Color is a physical phenomenon of light or visual perception
associated with the various wavelengths of the visual part of the Electromagnetic spectrum also called the Visible spectrum.
As a sensation experienced by humans and some animals, perception of color is a complex neuropsychological process. |
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Color is Light
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The color of light of a single wavelength or of a small band of
wavelengths is known as a pure spectral color or Hue.
Such pure colors are said to be fully saturated and are seldom encountered
outside the laboratory.
Light composed of vibrations of a single wavelength in the Visible spectrum differs qualitatively
from light of another wavelength.
This qualitative difference is perceived subjectively as the
Hue.
Light with a wavelength
of 700 nanometer is perceived as Red and light of 400 nanometer wavelength is perceived as Violet. |
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White Light
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White light is composed of Electromagnetic vibrations, the wavelengths of which are evenly distributed from 40 to 70
millionths of a centimeter.
If the intensity of these vibrations is strong ( great amplitude ) the light is white,
if the intensity is less, the light is weak and if the intensity is zero, the light is nonexistent or black.
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We need more knowledge
about color
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Looking around, a wide variety of colors
leap into our Eye's.
We are surrounded by an infinite variety of colors in our daily lives.
However, unlike length
or weight, there is no physical scale for measuring color, making it unlikely that everyone will answer in the same way when
asked what a certain color is.
For example, if we say "blue ocean" or "blue sky", each individual
will imagine different blue colors, because their color Sensitivity and past experiences will be different.
This is the problem with color. So let's study a little and determine what kind of color information would be useful.
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Color language
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If you show
a colored Object to five different people, you are bound to get five
different answers.
Color is a matter of perception and subjective
interpretation.
Looking at the same Object, people will draw upon
different references and experiences and express the exact same color in
vastly different words. Because their is such a wide variety of ways to
express a color, describing a particular color to someone is extremely
difficult and vague.
Verbal expression of a color is too complicated and
difficult.
However, if there was a standard method by which colors could
be accurately expressed and understood by anyone, color communication
would be smoother, simpler and exact. Such color language would eliminate
color-related problems. |
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Common and systematic
color names
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Words for
expressing colors have always changed with the times.
If we consider for
instance a red color, there are "vermilion",
"cinnabar", "crimson", "rose",
"strawberry" and "scarlet", to mention just a few.
These are called common color names.
By analyzing the color condition and
adding adjectives such as "bright", "dull"' and
"deep" we can describe the color a little more precisely. These
terms are called systematic color names.
Although there are a variety of
such ways to describe color, different people hearing just
"crimson" or "bright red" will still interpret such
expression in different ways.
So... verbal expression of colors is still not
accurate enough.
Then how should colors be expressed to avoid the
possibility of misunderstanding? |
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Light
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An apple
which looks so delicious under sunlight in front of the green grocer
somehow doesn't look so good under fluorescent light at home. Probably
many people have had such an experience.
Sunlight, daylight, candle light,
fluorescent light, tungsten light, et cetera; each type of
illuminant will make the same apple look different. |
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Observer
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The Sensitivity of each individual's
Eye
is slightly different; even for people considered to have "normal" color vision, there may be some bias toward red
and blue.
Also, person's eyesight generally changes with age.
Because of
these factors, colors will appear differently to different Observer's. |
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Size
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After
looking at small sample pieces and selecting wallpaper which look good,
people sometimes find that it looks too bright when it's actually hung on
the wall.
Colors covering a large area tend to appear brighter and
more vivid than colors covering a smaller area.
This is referred to as
area effect.
Selecting Object's which will have a large area based on color samples having a small area
may result in mistakes. |
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Background
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If an apple
is placed in front of a bright background, it will appear duller than when
it was placed in front of a dark background.
This is referred to as
contrast effect and is undesirable for accurately judging color. |
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Directional
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When
looking at a car, viewing the car from just slightly different angle can
make a point on the car appear brighter or darker.
This is due to the
directional characteristics of the car's paint.
Certain coloring
materials, particularly metallic paints, have highly directional
characteristics.
The angle from which the object is viewed and also the
angle from which it is illuminated, must be constant for accurate color
communication. |
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The wide variety of colors
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The wide
variety of colors seen every day are colors of lower saturation, that is,
mixtures of light of various wavelengths.
The Hue and the Lightness and the Saturation are the three qualitative
differences of physical colors.
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Devices
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A device
for producing and observing a spectrum visually is called a spectroscope.
A device for observing and recording a spectrum photographically is called
a spectrograph.
A device for measuring the various portions of the
spectrum is a spectrophotometer.
The science of using spectroscopes,
spectrographs and spectrophotometers to study color is called
spectroscopy. |
