Gamut

Gamut is originally a term used in connection with the Guidonian hand the total number of possible tones designated (from " Γ ut " pronounced " gamma ut ", or " gamut ", gamma = lowest note ut = highest tone ). Today, the term is associated with a color palette and is the set of all colors that represent a device (such as a monitor, printer, scanner, film), play or record can. Formally, the gamut of the body in the color space which can be adjusted with the device through internal color mixing.

Survey

Here is an RGB model with the three nominal primary colors of the visual system of the human eye (the large gamut of the horseshoe shape of the CIE model lies in the non-linear processing of the eye, the true colors of the receptors are in blue, green and yellow)

• A red five -color printing gamut ( yellow, cyan and magenta, two blue and green as a spot color, this would a pure black )
• Blue a typical Monitorgamut
• Green is the color gamut in the photographic ( analog ) film technology

Colors that can not be a device or can not be represented within a color model are outside its gamut. The saturated, bright green of the monitor can not display the printer, but it does not reach even by far the greens of nature. Another example is the pure red of the RGB color space, which is located in the CMYK model outside its gamut. Conversely, a monitor can be particularly yellow only either too light, or verbraunt ( desaturated ) represent, while as a process color is a basic color in the CMYK model.

• On the one hand increases the saturation to about two thirds of the distance from the center no longer: The monitor is actually not able to represent the truly color deep tones: the true Monitorgamut would be within the marked triangle
• On the other hand it shows the characteristic cloudy in yellow, cyan and magenta with a uniform distribution of the nominal RGB values ​​, because these two activated on the monitor through color dots ( sub-pixels ) are displayed for each pixel, and therefore have double luminance. The two-dimensional model represents only a projection of the color space in which the color deep tones of yellow, cyan and magenta and bright light are not covered by red, blue and green.

Law a true sRGB gamut in CIE1931 color model ( everything outside the triangle can not be displayed )

A fundamental task of managing color is the color gamuts of various devices to map to each other so that as little as possible, color displacements and demolitions occur. This process is called gamut mapping, and it is done by means of color profiles. The gamut mapping method to use puts the user firmly by the choice of rendering intents.