Basic Facts On Full Color Printing

A full color printing is the reproduction of an image or text in color instead of the simple black and white or monochrome printing.

While there are many techniques for reproducing images in color, specific graphic processes and industrial equipment are used for mass reproduction of color images on paper. In this sense, full color printing involves reproduction techniques suited for printing presses capable of thousands or millions of impressions for publishing newspapers and magazines, brochures, cards, posters and similar mass-market items.

In this type of industrial or commercial printing, the technique used to print full-color images, such as color photographs, is referred to as four-color-process printing, because four inks are used: three primary colors plus black. The subtractive primary ink colors are cyan, a bright blue; magenta, a vivid red-purple; and yellow; which are abbreviated as CMYK.

Two graphic techniques are required to prepare images for four-color printing. In the pre-press stage, original images are translated into forms that can be used on a printing press, through color separation and screening or halftoning. These steps make possible the creation of printing plates that can transfer color impressions to paper on printing presses based on the principles of lithography.

The process of color separation starts by separating the original artwork into red, green, and blue components (for example by a digital scanner). Before digital imaging was developed, the traditional method of doing this was to photograph the image three times, using a filter for each color. Thus, the desired result is three grayscale images, which represent the red, green, and blue (RGB) components of the original image.

The next step is to invert each of these separations. When a negative image of the red component is produced, the resulting image represents the cyan component of the image. Likewise, negatives are produced of the green and blue components to produce magenta and yellow separations, respectively. This is done because cyan, magenta, and yellow are subtractive primaries which each represent two of the three additive primaries (RGB) after one additive primary has been subtracted from white light.

Todays digital printing methods do not have the restriction of a single color space that traditional CMYK processes do. Many presses can print from files that were ripped with images using either RGB or CMYK modes. The color reproduction abilities of a particular color space can vary; the process of obtaining accurate colors within a color model is called color matching.

Currently, there is also an emerging method of full color printing or aptly known as six-color process printing, which adds orange and green to the traditional CMYK inks for a larger and more vibrant color range. Unfortunately, such alternate color systems still rely on color separation, halftoning and lithography to produce printed images.

Color printing can also involve as few as one color ink, or multiple color inks which are not the primary colors. Using a limited number of color inks, or specific color inks in addition to the primary colors, is referred to as spot color printing. Generally, spot-color inks are specific formulations that are designed to print alone, rather than to blend with other inks on the paper to produce various hues and shades.

The range of available spot color inks, much like paint, is nearly unlimited, and much more varied than the colors that can be produced by four-color-process printing. Spot-color inks range from subtle pastels to intense fluorescents to reflective metallics.

A full color printing involves a series of steps, or transformations that can generate quality color reproduction for any printed material needed.