COLOR

Color is the foremost element in art that taps into our emotions. To the average person, a mysterious or misunderstood work of art might be appreciated on its color aspects alone. Our culture, our education, our environment, and our experiences all shape our perception of color and its expressive power. Color can make our hearts beat faster. It can dampen our spirit, sooth or send us away in disgust. How is it that we see color?

Without light we don’t see color. When light is weak, all colors seem to be moving toward gray. In bright light, color is brilliant, such as the bright blue of the sky at a high altitude on a sunny day. Color is based on three concepts: our color perception (how our eyes and brains process color information), the relationship of color and light (called additive color), and a system of surface color and colored substances called subtrative color. This system describes the way light reflects from and is absorbed into colored surfaces. So color has a physical, psychological, and chemical aspect.

It is this system that is most difficult for art students. It is confusing to think of color as light, but compouter art and web graphics have made the additive color system as important to artists as the subtractive system of paints, inks and dyes.

COLOR PHYSICS

Rays of light are composed of waves that vibrate at different speeds. We respond to these different wavelengths with our sense of vision. In approximately 1665, Sir Isaac Newton, an English physicist and mathematician, passed a light through a prism. A spectrum of color was bent, or refracted, and cast upon white paper. He then project the spectrum back through a prism to re-form white light. He concluded that the refraction revealed separate colors called hues. Those seven distinct hues were red, orange, yellow, green, blue, indigo, and violet. These make up the spectral hues we see in a rainbow. Newton later added red-violet to this spectrum connecting the band to itself and forming a continuous color circle. The color circle functions as a device to better understand the relationships between the spectral hues.

The full electromagnetic spectrum is much larger than the portion containing the visible spectral hues. In 1860, James Maxwell, a Scottich physicist presented the theory that visible light was an electromagnetic phenomenon. It does not need any material for heat transmission. Out of our visible spectrum are the infra red and ultra violet light, microwaves, radio, e-rays, gamma, etc.

ADDITIVE COLOR

The television industry uses additive color mixing, color monitors, video production, neon, laser light, all work with additive color. The three color primaries of color light are red, blue, and green. When collected all together these three primaries make white light. We refer to this as RGB. Mixtures of the additive primaries form secondary hues of cyan (blue), magenta, and yellow. These are the same colors as the primaries of the process colors, CMY. Secondary hues are a mixture of two primary hues. Process colors are used in the printing industry together with black to create all the colors we see in printed media. Black is the K or 'key' in the CMYK reference.

The diagram on the right is the additive color wheel with the primaries, RBG and the secondaries in between.

SUBTRACTIVE COLOR

Subtractive color refers to both surface color and the physical color of pigments, dyes, and inks. So it has to do with how we see color and also how color materials are mixed. How is it that we distinguish a single color of an object? Each object has a quality that allows it to absorb some wavelengths of light and reflect others. We see a lemon as yellow because it absorbs all wavelengths except yellow. Artist’s pigment also has this ability and when applied to a surface it will give that surface the same characteristics. The artist is working then with reflected light known as subtractive color. When the subtractive color primaries of blue, red, and yellow are mixed together, the color produced is theoretically able to absorb all the wavelengths of light, and consequently subtract (or absorb) all light, therefore appearing as black. In actuality, a mixture of all the primaries will produce a dark brown-gray, rather than black due to impurities in the pigment.

COLOR MIXING - SUBTRACTIVE COLOR - PIGMENT WHEEL The spectrum contains red, orange, yellow, green, blue, blue-violet, and violet with hundreds of subtle variations. This range is available in pigment also. Many colors can be mixed from two colors. Three colors cannot be mixed. These are the three primaries of red, yellow and blue. When primaries are mixed in pairs, all other colors can be created. Mixing any two adjacent primaries produces a secondary. The secondaries are green, orange, and violet. Mixing a secondary with a nearby primary produces an intermediate. Some texts call this a tertiary -- but a true tertiary lies on the inner part of the color wheel and has a lower chroma.

The three color subtractive primaries are equally spaced on this wheel with yellow on top. These colors form an equilateral triangle, called a primary triad. The three secondary colors are placed between the primaries, creating a secondary triad composed of orange, green, and violet. Tertiary colors placed between each primary and secondary color create equally spaced units known as intermediate triads. This results in a twelve-color wheel. Hues directly opposite each other afford strong contrast and are called complementary colors.

Because we do not distinguish color in black, white, and gray, we call them neutrals. Neutral are achromatic, meaning they contain no chroma or hue. Neutrals define our concept of light and dark. Neutrals relate to the wheel as entities of value and as hue effectors. They can change the value or saturation of any given hue. The steps you studied in the lesson on value were an achromatic scale. It is aligned with the color circle. The chart below is the inherent value equivalent of the 12 hues on the pigment wheel.

Look back at the additive wheel and notice that the complementary pairs of the additive wheel, RGB, are CMY, the process colors. Remember the three primaries in the process wheel are Cyan, Magenta and Yellow - a slight variation on the pigment wheel. Artists who work with paint mainly use the pigment wheel as their model. Artists who work in the fields of printing and dyes, often use the process wheel, and artists who work with light (video, electronic media, television, computer graphics, web design, stage lighting) utilize the additive wheel. Artists and designers should be able to work with both systems, additive and subtractive.

ATTRIBUTES OF COLOR HUE The term hue refers to the name of an identifiable wavelength in visible light such as red, green, etc. Hue designates the particular spectral color on the visible spectrum and on the color wheel. Color can be any vairiation on a hue or neutral. Colors are chromatic (contain some hue). The identity of any color should refer to its spectral hue; for instance, blue mixed with black if referred to a shade of blue. A descriptive name for this color would be navy blue. Descriptive names are used by the commercial paint and product industry. Some names refer to pigments as well. VALUE Value refers to the quantity of light a color reflects, or how light or dark it is. Each color in its brightest state has a normal value, which indicates the amount of light it reflects. It can be made lighter or darker by adding white or black without changing the color. The simplest way to lighten a hue is to add white, and conversely, the simplest way to darken it is to add black. A hue plus white is a tint, and a hue plus black is a shade. The chart at the right is a value scale of 17 steps with tints and shades of 12 hues. INTENSITY Intensity is the third attribute of color. It is sometimes called saturation or chroma. It refers to the quality of light in a color. We distinguish a brighter tone from a duller one. The highest point of saturation, or the purest color is found in the spectrum produced by a beam of light. However, the artist’s pigment that comes closest to resembling this color is said to be at maximum intensity. There are several ways to change the intensity of a hue. One of the most interesting is through simultaneous contrast. When a hue is placed next to its complement, each color will be affected by an increase in intensity. Other methods require the mixing of pigments. This will automatically lower the intensity of a hue. Adding white will lighten the value of a hue, but will also lower the intensity. A hue can have its intensity lowered without a change of value. This can be accomplished by mixing a neutral of the same value as the hue. Adding complements will also lower the intensity of a hue and produces a lively character not present when the same hue is neutralized with a gray pigment. Simultaneous contrast in its simplest state is the principle of color interaction, which states that the larger color space/shape will act upon the smaller color space/shape by adding its complement into the smaller space/shape. Can you determine how that works in the above diagram? This interaction will apply to value as well as hue complements.