Learning more about RGB & CMYK

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What is RGB Color?

Digital cameras and scanners and create images using combinations of just three colors: Red, Green and Blue (RGB). These are the primary colors of visible light and this how computers and televisions display images on their screens. RGB colors often appear brighter and more vivid specifically because the light is being projected directly into the eyes of the viewer.

This is an “additive” process in which the three colors are combined in different amounts to produce various colors. It is called “additive” because you must add varying amounts of two or more colors to achieve hues and values other than the three basic red, green and blue colors.

Computer monitors and televisions vary the amount of each color from 0 to a maximum of 255. Equal maximum amounts of all three colors (often expressed as R255, G255, B255) creates white. The absence of all three colors (R0, G0, B0) creates black. Equal amounts of all three colors somewhere between 0 and 255 will create varying shades of gray.

What is CMYK or Process Color?

Professional printing presses print full color pictures by using the colors Cyan, Magenta, Yellow and Black (CMYK). In this “subtractive” process the various inks absorb the light reflected from the underlying white paper to produce the colors that your eye sees. The colors that you see are those colors which were not absorbed by the ink. It is called subtractive because when you subtract the other colors, the color that is left is the color that you see.

In the CMYK color system equal proportions of Yellow ink plus Cyan ink produces Green, Yellow ink plus Magenta ink produces Red, and Cyan ink plus Magenta ink produces Blue (actually more like purple to most eyes). Various color shades and values are achieved by varying the relative amounts of the four colors. Black ink is added to improve the quality of 3-color blacks, to provide added detail to images, to speed drying, and to reduce overall ink costs, thus the name: Four Color Process.

RGB Must be Converted to CMYK Color in Order to Print

At some stage your RGB file must be translated to CMYK in order to print it on a textile or non – textile objects . It is best if you do the RGB to CMYK Conversion of your images. You will have more control over the appearance of your printed piece if you convert all of the images from RGB to CMYK before sending them to us. Be aware that it is possible to create colors in RGB that you cannot reproduce with CMYK. These are beyond the CMYK color range or “out of the CMYK color gamut”.

When we receive RGB images in a job we instruct our RIP software to make the conversion to CMYK. The RGB to CMYK conversion table tries to map colors to get as close as possible to the appearance of the original. We think that it does a very good job but it is possible that it might not be to your liking.