Natural Color System
The Natural Color System ( NCS, and NCS color system ) is a standardized color system, which is based on human color perception ( color perception ).
History
Based on the theory of opponent colors ( Opponententheorie ) by Ewald Hering in the 19th century developed the physicist Tryggve Johansson 1937-1939 its own color system, which was the basis for the color atlas of Sven Hesselgren with more than 500 colors. The color atlas has been refined by Anders Hård in the modern NCS system. 1946 was founded by Anders Hård the Scandinavian Colour Institute in Stockholm, which holds the rights to the NCS system. NCS is a registered trademark of the Scandinavian Colour Institute (Scandinavian Colour Institute ), headquartered in Stockholm, Sweden.
NCS color theory
The Natural Color System starts from the four chromatic basic colors that are "pure" perceived by the latter as - Yellow ( Y ), green ( G ), red ( R ) and blue ( B). The colorimetric properties of these basic colors were determined under laboratory conditions using a statistically relevant number of test persons. There are those colors that are perceived as being free of other colors. For example, each ( normal vision ) define a human being blue, which is perceived as being free from red or green. In contrast, no yellow can imagine, including blue and contains no green, red. This color pairs are therefore arranged as complementary colors in a circle facing each other.
All other colors are seen as a transition between these colors and given in percentages. Then there are the achromatic colors black and white.
Similar to the Ostwald's double cone contains the saturated colors on a color wheel, which forms base tapering for a up ( pure white) and bottom ( pure black ) cone simultaneously. On the outside of the upper cone are the colors. By tinting with white, on the lower cone those arising by tinting with black Inside of the double cone colors are found, which are tinted with different percentages of black and white. If you cut from the double cone along the white-black axis a (very thin ) piece of cake out, the result is a shade same area, in which along the top edge black same colors ( = color with the same amount of black ), along the lower edge white same color ( = colors with the same amount of white ) and along the black-white axis read the same pure colors ( = color with the same degree of purity ).
The NCS color identification is divided into two parts: The first part gives the density of black and color ( ie color saturation ) of a color again, the second part of the position of the basic hue on the color wheel YRGB. All numerical values are thereby of 100 from the maximum value and minimum value as 0. All color values in the NCS system are linear ( not logarithmic) and reported as theoretical values . The colors that can not be produced with existing pigments are not present in the NCS color charts.
A 30 % saturated, slightly reddish yellow tending with 30% hydrogen Black would share in the NCS system consequently NCS 3030 - Y30R called:
Colors that lie directly on the gray axis obtained, instead of the color code of an N for neutral, ZB NCS 5000 -N, a medium gray.
A preceding S ( in the above example, NCS S 3030 - Y30R ) means that the corresponding color value of the Second Edition, that the revision of 1995 comes from.
The NCS system is one of the few color systems used in the world (next to the RAL design system with 1688 colors and the Pantone Matching System ) in which organized strictly currently 1950 color pattern, named by letters and numbers, are available. While the NCS Edition 2 ( used only environmentally safe pigments) comprised 1750 colors were recently still 200 - lighter tones - about what the current number 1950 NCS colors together.