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About WhiteWhite is a color that has high brightness but zero hue. More accurately, white contains all the colors of the spectrum and is sometimes described as an achromatic color. By comparison, black is also an achromatic color, and, strictly speaking, is the absence of visible light.Shades of WhiteThere are a number of words that symbolize white, or various shades of the color white, eg: alabaster, antique white, beige, chalk, cornsilk, cream, ghost white, ivory, lily, linen, milk white, old lace, paper, pearl, porcelain, seashell, silvery white, smoke, snow, whitewash.
White LightUntil Newton's work became accepted, most scientists believed that white was the fundamental color of light; and that other colors were formed only by adding something to light. Newton demonstrated that White was formed by combining the other colors. In nature, white light is produced by incandescence, a process where light is emitted by a substance at relatively high temperaturesThe impression of white light can be created by mixing light from appropriate intensities of the three primary colors red, green and blue, (a process called "additive mixing"), but it must be noted that the illumination provided by this technique has some differences from that produced by incandescence In the science of lighting, there is a continuum of colors of light that can be called "white". One set of colors that deserve this description are the colors emitted via the process of incandescence. For example, the color of a black body at a temperature of 2848 kelvins matches that produced by domestic incandescent light bulbs. It is said that "the color temperature of such a light bulb is 2848 K". A higher color temperature corresponds to a bluer light, a lower color temperature to a yellower light. This can be seen clearly by comparing halogen lights to standard filament bulb lights which operate at a lower temperature. The white light used in theatre illumination has a color temperature of about 3200 K. Daylight has a nominal color temperature of 5400 K (called equal energy white), but can vary from a cool red up to a bluish 25,000 K. Standard whites are often defined with reference to the International Commission on Illumination's (CIE's) chromaticity diagram. These are the D series of standard illuminants. Illuminant D65, originally corresponding to a color temperature of 6,500 K, is taken to represent standard daylight. Computer displays often have a color temperature control, allowing the user to select the color temperature (usually from a small set of fixed values) of the light emitted when the computer produces the electrical signal corresponding to "white". The RGB coordinates of white are 255 255 255. Most video cameras can adjust for color temperature by zooming into a white object and setting the white balance (telling the camera "this object is white"); the camera then shows true white as white and adjusts all the other colors accordingly. White-balancing is necessary especially indoors under fluorescent lighting and when moving the camera from one lighting situation to another.
PaintIn the coloring of paint, ink, plastic, fabric and other material, a pigment is a dry colorant, usually an insoluble powder. There are both natural and synthetic pigments, both organic and inorganic ones. Pigments work by selectively absorbing some parts of the visible spectrum whilst reflecting others.In painting, white can be created by reflecting ambient light from a white pigment (a pigment that reflects most of the light in the spectrum). White pigment, when mixed with black produces gray.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "White" and from http://www.white-on.com
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