In the arts of painting, and photography, color
theory is a set of basic rules for mixing color to achieve a desired
result. As pigment and light are different in terms of how they
combine to create colors, so too are the rules for dealing with
each. White light is composed of the three primary hues, while combining
these same hues in pigment will produce a black color.
Goethe's Colour Wheel
RYB Color Wheel
RGB Color Model
CMY Color WheelGoethe proposed a symmetric color circle, which comprises
both the Newtonian and complementary spectra. In contrast, Newton's
color circle, with seven colors subtending unequal angles, did not
exhibit the symmetry and complementarity that Goethe regarded as
essential characteristics of color. For Newton, only spectral colors
could count as fundamental. Goethe's more empirical approach led
him to recognize the essential role of (nonspectral) magenta in
a complete color circle.
In the RYB color model, red, yellow, and blue are
the primary colors, and in theory all other pure colors can be created
by mixing red, yellow, and blue paint. Many people learn a bit about
color in elementary school by mixing paint or crayons in these primary
colors. The RYB color model is used mostly with traditional artistic
and painting concepts, and rarely used outside of paint-pigment
mixing. But even when used as a guide for paint-pigment mixing,
the RYB color model doesn't accurately represent what colors would
result from mixing the three RYB primaries. As of 2004, scientists
know that this set is incorrect, but it continues to be commonly
used in art.
Mixing colors of light, usually Red/Green/Blue,
is done using the additive color system (also referred to as the
"RGB Model" or "RGB color space"). All the possible
colors that can be created by mixing these three colored lights
are referred to as the gamut of those particular lights. All these
colors when mixed together in equal portions create white; when
no color of light is present, one perceives black. Additive color
applies to computer monitors, television, and video projectors,
all of which use combinations of red, green, and blue phosphors.
For printing purposes, the colors used are cyan,
magenta, and yellow; this model is called the "CMY model".
In the CMY model, black is created by mixing all colors, and white
is the absence of any colors (assuming white paper). As colors are
subtracted to produce black, this is also called the subtractive
color model. A mix of Cyan, Magenta, and Yellow actually gives a
muddy black so normally true black ink is used as well; when black
is added, this color model is called the "CMYK model."
More recently, it has been shown that the CMY color model is also
more accurate for pigment-mixing.
A much more detailed discussion of color models,
particularly as they apply to color for computer displays, can be
found in the color space article.
It should be noted that only fictional "primary"
colors can mix all possible colors. These primaries are arbitrary
concepts used in mathematical models of color vision that do not
represent real color sensations or even real nerve impulses or brain
processes. In other words, all perfect "primary" colors
are completely imaginary.
On the other hand, any three (or four or five or
six) real "primary" colors cannot mix all the colors in
any medium, and this is always true no matter which "primary"
colors are chosen and no matter which medium — inks, paints,
dyes, filters, phosphors, artificial lights, or monospectral lights
— is used to mix the colors. In other words, all mixable "primary"
colors are incomplete or imperfect.
The Color Wheel
Traditionally colors are represented on a wheel of 12 colors: three
primary colors, three secondary colors (created by mixing primary
colors), and six tertiary colors (created by mixing the primary
and secondary colors). Artists use a traditional color wheel based
on the RYB model (red/yellow/blue) with secondary colors of orange,
green, and purple. For all computer-based color, a wheel based on
the RGB model is used; this encompasses the CMY model as well since
cyan, magenta, and yellow are the secondary colors for red, green,
and blue. (Conversely the secondary colors for cyan, magenta, and
yellow are red, green, and blue.) In the RGB/CMY color wheel, orange
is a tertiary color between red and yellow and purple is a tertiary
color between magenta and blue.
Tints and Shades
The color wheel is based on "pure" colors; for every color
there are also darker and lighter versions. Darker versions are
produced by adding black or removing light, and are called shades;
they are sometimes also called "deep" or "dark"
colors. Dark shades of yellow, oranges, and some reds are typically
called browns. Lighter versions are produced by adding white or
more light, and are called tints; they are also sometimes called
"pale" or "light" colors. Very light tints are
also often referred to as "pastel" colors; light tints
of some reds, oranges, and yellow are tans.
Color wheel with shading for color picking.
Color Harmony and Color Schemes
Harmonious colors are colors that work well together, that produce
a color scheme that looks attractive; the color wheel can be used
as a valuable tool for determining harmonious colors. Complementary
colors are colors directly across from each other on the wheel.
These are typically colors that will produce a strong contrast.
Split complementary colors are those on either side of a complementary
color; these colors contrast, but not as strongly as complementary
colors. Triad colors represent three colors equidistant on the color
wheel; this typically provides a balanced color scheme with reasonable
contrast. Analogous colors are colors next to each other on the
color wheel. They typically harmonize well but may not provide enough
contrast, and are perhaps best used in conjunction with a complementary
color. Monochromatic colors are all shades and tints of the same
Cool and warm colors
Warm are all those that have a yellow undertone, such as bright
red, oranges, yellows, and green-yellows, and are typically thought
to express warmth, comfort, and energy. These colors also tend to
make things stand out and advance towards you from the page or screen.
Cool colors have a blue undertone, and include violets, blues, aquas,
and greens. When they are used together, cool colors seems to move
away from the viewer, and express coolness, detachment, stability,
Black, gray, and whites are neutral; browns, beiges, and tans are
sometimes considered to be neutral as well. Neutral colors are intended
to send no messages but often work harmoniously with other colors.
They are sometimes thought of as colors "off the color wheel".
Schemes from Nature
Combinations of colors found in nature often work well as color
schemes even if they don't fit specific patterns discussed above;
examples of these schemes include "autumn colors" and
Color in Painting
In painting the different color wheels are used as tools to teach
beginners the essential relationships between color hues. It should
be noted that the organization of colors on the various color wheels
is very subjective, dependent on whether a particular color wheel
is used for color perception, color psychology, or color mixing.
Traditional color theory using the RYB color wheel
states that the primary colors (red, blue, yellow) combine to form
the three secondary colors (purple, green, orange). A primary color
will have a secondary color for its opposite — ergo red's
complement is green, blue's is orange, and yellow's is purple. Adding
a complementary color to a color on the canvas is the traditional
technique for making shadows, as well as for choosing a balance
of color overall, so that the eye does not tire from an overuse
of red, for example.
Unfortunately, when used in practice, combining
primary colors using the RYB color wheel often results in secondary
colors that lack vibrancy or are "muddy" — appear
as if they are "dirty" and turning brown. Mixing complementary
colors does result in a darker color, but the resulting color may
appear dull and muddy as well.
Mixing pigments using the CMY color wheel greatly
reduces this problem. Combining CMY primary colors (cyan, magenta,
and yellow) forms the three CMY secondary colors (blue, red, and
green) in a more vibrant, purer form than the RYB color wheel. Complements
around the wheel — cyan opposite red, magenta opposite green,
and yellow opposite blue — are more properly matched, and
when combined result in neutral dark grays and blacks instead of
dark browns or muddy blacks.
Although in theory, one should be able to mix all
colors using the CMY color wheel using just the pure pigments of
cyan, magenta, and yellow, the mixed colors usually are still duller
than their pure primary counterparts. This is especially apparent
between cyan/magenta, and yellow/cyan. In order to obtain a more
vibrant version of a mixed secondary color, one would replace the
dull mixed hue with a more vibrant natural pigment secondary color
of the same hue. For instance, mixing primaries hanza yellow and
phthalocyanine cyan — effectively yellow and cyan —
will result in a dull blue-green secondary color. In order to achieve
a more vibrant blue-green, the natural pigment phthalocyanine green
would be used. By replacing mixed secondary colors with natural
pigment secondary colors, mixed tertiary colors will be more vibrant
than mixed from the primaries alone.
In most color theories, "shadows" generally refers to
a general choice between adding black pigment, or using a complementary
color to contrast a color, thereby making it darker by mixture or
by optical illusion. The reason is that adding black to make a shadow
tends to flatten the painting —neutralizing any dynamic color
interactions that would otherwise occur. Adding a complement, accomplishes
the task of defining the darker area, and at the same time, adds
another color, creating a more realistic and dimensional look.
Depending on the quality of the paint, the balance between colors
varies greatly with pigment. One way to test the quality of oil
paints is to make a sample of black by mixing the primary hues.
To produce black, blue and red are mixed to a dark purple, which
is gradually bent toward a colorless black by adding smaller amounts
of yellow. Testing the balance of the mixture simply requires separating
a small portion and adding white spreading the grey out on the palette.
If the grey is colorless, then the black is pure. Poor pigment quality
makes a muddy, purplish/greenish glob, while better paints will
blend to black or very close to it.
The paintings are the excellent portrayal of the events and scenes
that we see around us. The painters are the best cameras of the
world. They reproduce many different types of pictures. They even
draw imaginary pictures that do not exist in this world. We tend
to use both thinned oil paints and dense oil paints. Masterpieces
can be dyed more than once, but each time it may be different from
the existing paintings.
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