CMYK Explained

CMYK printing uses a method called half-toning to create different intensities of colour while saving on ink. The technique has been used by printing presses since the 1850s and was adapted for the CMYK model to expand the colours that could be made.

The basic technique involves using little dots instead of solid blocks of ink. These little dots are small and spaced evenly apart so that the human eye sees it as a solid colour. If you look closely at the images printed in most newspapers, you’ll see that those solid pictures are actually comprised of these small dots. It’s most noticeable on newspapers as the thin paper means the less ink the better, and the cost of printing in such quantities also means the less ink the better!!

Interesting but unintended visual effects can happen if the layers of dots are aligned. To prevent these undesirable effects, the dots are printed at a slant on four different angles

CMYK black + white

When you have 100% of all colours (C 100%, M 100%, Y 100%, and K 100%) it creates solid black. In contrast, when you have 0% of all colours (C 0%, M 0%, 0%, Y, and 0% K), everything is subtracted, and your print will come out completely blank.

It is possible to create black and white colours by just using K, but if you are looking for more vibrant tones or shades of grey, you’ll achieve better results using all four colour elements. For example, what is referred to as “rich black” uses C 50%, M 50%, Y 50%, and K 100%.

This concept is true for all colours. If only one of the four possible primary colours is used (for example 60% C, 0% M, 0%, Y, and 0% K) the underlying material tends to shine through.

The future of CMYK

In 1956, Pantone asked a chemist to reduce the complexity of their printing process. The ink supply was reduced to a simpler system, using a smaller number of inks to produce a boundless range of colours. Their greatest contribution to the printing industry was to introduce the Pantone Colour Matching System.

To the majority of ink manufacturers worldwide, Pantone is considered standard. Even though most Pantone colours cannot be achieved from mixing the CMYK colours alone, the company recognizes its significance in the industry and indicates which ones can be reproduced on the CMYK model. Interestingly, Pantone uses only 14 pigments to create 1,114 unique colours, and they add new colours each year.

Today, an emerging method of full-colour printing is the six-colour printing process. This method adds orange and green to the traditional CMYK inks for a much more expansive, and vibrant, colour range.

Even though this method is more advanced in terms of numbers of colours, it still relies on traditional techniques like colour separation, halftoning, and lithography.

Extended Colour Gamut

In 2015 Pantone introduced its expanded Gamut coated guide, which introduces a seven-colour printing process. This includes CMYK colours, orange, green, and violet.

The ‘Extended Colour Gamut’ is meant to increase the efficiency with which colours are created. What was done in the ink room can now be done in prepress. This process is becoming mainstream and, as a result, it is a standardized reference for brand owners, designers and printers.

Hopefully this has enlightened you just a little bit and given you a better understanding of the CMYK printing process. For more information on colour and its various intricacies, stay tuned for articles on RGB and more!!