How many colors can CMYK make

CMYK - the secret of the four colors

The use of colors for presentations on screens and in print follows the physical characteristics of the human eye. This is particularly sensitive to three light wavelengths. Exactly these colors red, green and blue are used in the RGB color space. This ensures a color-balanced reproduction on color monitors.

In the printing process, on the other hand, white paper is usually printed on. Paper is not transparent and therefore does not let light through. The four printing colors cyan, magenta, yellow and black - CMYK - are used in the industrial offset color printing applied to the paper one after the other. The printing does not take place over a large area, but with very small, closely spaced dots that are perceived by the human eye as a colored image from a normal viewing distance. In industrial offset printing, 300 dots per inch (dpi) printed, converted into the metric system, this is 11.8 printing dots per millimeter. These pressure points are of different sizes depending on the desired thickness of the paint application. If a color component is equal to zero percent, there is no dot at this point and therefore no color.

At Color ink printers Tiny drops of ink are thrown onto the paper as pressure points, which are also close together. The point size is 0.3 to 0.4 millimeters. The sum of the individual droplets in the CMYK colors then creates the “illusion” of a colored image. A color laser printer delivers the same result, but in a different way. There are four electrically charged drums that are discharged by a laser beam in the places where no toner from one of the four CMYK cartridges should adhere. The remaining charged areas are then thinly coated with the toner colors. These coated print pixels are successively transferred to the paper and fixed there with heat.

These three examples - offset, color ink and color laser printing - illustrate the requirements for the precision of the printing machines. In the following you will find out how the colors are divided up and used for this.