designbymyself

Cyan Magenta Yellow, Key (Black), or often abbreviated as CMYK is the process of mixing pigments commonly used printing. Process Cyan Ink, Process Cyan, Process Yellow, Black mixed with the process of composition and color accuracy to produce exactly as desired. Even if some time is required, this color (CMYK) can easily be reshaped. CMYK color system is also used by many printers because of the economic underclass. This model, either in part or whole, are usually imposed in the picture with white background color (this color is selected, because he can absorb a certain length of the light structure). Such a model is often known as the "subtractive", because the colors to reduce color of white light.

In another model of "color additive", as well as RGB (Red, Green, Blue), white color to the color combination of additional primary colors, while the black color may occur without any light. In the CMYK model, the opposite applies: the white color becomes natural color of the paper or a background color, whereas black is the color combination of primary colors. To save money to buy the ink, and color to produce a darker black, was made a special black color replaces the combination of Cyan, Magenta and Yellow.

There are terms in Photoshop Gamut Warning, Gamut is a term for the area that could be covered by a particular color system. The term is out of gamut colors that can not be represented by the proportion of the basic colors you want to use the system. Problems out of gamut often occurs in the conversion of CMYK colors with RGB colors. Although designed to provide accurate color, the color region formed by the CMYK color system sometimes is not as wide as RGB color range. For example RGB primary color red is out of gamut of the CMYK color system. Many ways have been sought to pursue this difference, for example by using color lab system.

source: wikipedia