What do CMYK and RGB stand for? What are the differences?

CMYK and RGB. Pretty much everyone who has ever stood in front of the printer at home, for example replacing the printer cartridges, will eventually have read them before. But what does CMYK and RGB stand for? Why are there different color spaces and why do the colors look different on the printed product than on the screen? Questions that you can answer after our contribution.

CMYK – the color space for printed products

CMYK stands for the colors cyan, magenta, yellow and black. The K for black refers to the key plate, the black printing plate.

CMYK printing is very common in the printing industry. Especially in Europe. This is also often referred to as “printing on a Euroscale”. Especially in the USA, this stands for European offset printing.

Inkjet printers and color laser printers generally work with the CMYK color system.

In recent years, photo printers with additional colors have been increasingly available on the market. These additional colors are gradations of cyan and magenta.

RGB – the color space for digital media

The abbreviation RGB stands for red, green and blue. It is a color model with which certain color values ​​are given. With the three primary colors red, green and blue, pretty much all colors can be represented. These are mixed in a certain ratio. Around 16 million different colors are possible.

The RGB color space is used for monitors, smartphones and televisions. On the display blue, red and green points of light are close together.

CMYK und RGB - Farbraum im Vergleich

What is the difference between RGB and CMYK?

For example, if a digital color image is printed, the image must be converted from RGB to CMYK. Since not all colors of the RGB color space are available in CMYK, the non-existent colors are converted into the closest CMYK color.

The greatest variance lies here, since the RGB color space can display a much larger number of colors than the CMYK color space. If the print data is not created in CMYK, so-called color deviations result. This results in the color differences mentioned at the beginning between a print product and the display on the screen.

This can be easily avoided by generally creating your print data in CMYK.

CMYK limit value – interesting to know

When printing in the CMYK color space there is the so-called limit value. As the name suggests, this must not be exceeded. The sum of the individual colors is relevant. An example:

In detail the overall limit value says that the sum of all four process colors (cyan, magenta, yellow, key), for coated paper, may not be more than 300% at any point on the printed sheet. A color value like 80C / 90M / 90Y / 70K therefore would be improper because the sum of the values ​​results in a total order of 330%.

Why is there a limit?

The limit depends on the printed paper, because it defines how much color a paper can take. While a high-quality paper application of 350% is possible with many high-quality papers, newspaper printing has already reached its limit at approx. 240%.

The best thing to do is to ask at your printing house about the appropriate limit before printing.

Did you like our excursion into the color theory? If you are interested in topics related to printing, we can recommend our newsletter to you. Register now and stay up to date.