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Under Color Addition
In four-color printing The CMYK color model (also known as process color, or four color) is a subtractive color model, based on the CMY color model, used in color printing, and is also used to describe the printing process itself. The abbreviation ''CMYK'' refers ... (or more), under color addition (UCA) is a technique for darkening areas of the printed image by adding colored inks. It is meant to achieve the same results as under color removal, but from a different starting position. Under color removal replaces colored inks in selected areas with black ink to achieve a darker appearance, whereas with under color addition, small portions of the three colors are added to these areas instead of, or in addition to, using black ink. UCA is used to reduce the speckle effects of dithering, especially with very light colors. Without UCA, a very light grey would consist of infrequent black specks that might be individually noticeable. With UCA, the specks are lighter and 3x mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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Four-color Printing
The CMYK color model (also known as process color, or four color) is a subtractive color model, based on the CMY color model, used in color printing, and is also used to describe the printing process itself. The abbreviation ''CMYK'' refers to the four ink plates used: cyan, magenta, yellow, and key (most often black). The CMYK model works by partially or entirely masking colors on a lighter, usually white, background. The ink reduces the light that would otherwise be reflected. Such a model is called ''subtractive'', as inks ''subtract'' some colors from white light; in the CMY model, white light minus red leaves cyan, white light minus green leaves magenta, and white light minus blue leaves yellow. In additive color models, such as RGB, white is the ''additive'' combination of all primary colored lights, and black is the absence of light. In the CMYK model, it is the opposite: white is the natural color of the paper or other background, and black results from a ful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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Under Color Removal
In printing, under color removal (UCR) is a process of eliminating overlapping yellow, magenta, and cyan that would have added to a dark neutral (black) and leaving the black ink only, called a ''full black'', during the color separation process. Under color removal is used in '' process color'' printing. Black ink used to add details and darkness in shadowed areas is called a ''skeletal black''. With current ink technology, the total CMYK ink in the shadows refuses to stick after it reaches the dark shadows (usually above a 250% total CMYK coverage), and begins to peel off. To prevent this, printers developed UCR, in which neutral shadowswhich would have normally been produced by overprinting the four inks ''cyan'', ''magenta'', ''yellow'' and ''black'' on top of each other (high ink coverage)are replaced with the single layer of ''black''. UCR removes the color inks ''under'' the black, resulting in a single layer of ink which sticks to the sheet better, and saves on the consum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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Rich Black
Rich black, in printing, is an ink mixture of solid black over one or more of the other CMYK color model, CMYK colors, resulting in a darker tone than black ink alone generates in a printing process. A typical rich black mixture might be 100% black, 50% of each of the other three inks. Other percentages are used to achieve specific results, for example 100% black with 70% cyan (C), 35% magenta (M), and 40% yellow (Y) is used to achieve "cool" black. "Warm Black" is 35%C, 60%M, 60%Y, and 100%K. The colored ink under the black ink makes a "richer" result; the additional inks absorb more light, resulting in a closer approximation of true black. While, in theory, an even richer black can be made by using 100% of each of the four inks, in practice, the amount of non-black ink added is limited by the wetness that the paper and printing process can handle. (A safe and practical rule of thumb is that ink coverage should not exceed 240% on normal papers. Papers that "pick", such as low-e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |