What are CMYK Separations?

Commercial print, be it magazine, newspaper, brochures, etc. uses a four-colour printing process called CMYK. What does CMYK stand for? Cyan, Magenta, Yellow and Key (which is Black).

CMYK printing works by separating the colours, for example, from a photograph, into 4 separate coloured inks using individual printing plates. When four coloured plates are printed onto a sheet of paper, they create an optical effect that to the viewer, looks like the original image.

CMYK illustration

The diagram above demonstrates how the different colours of the spectrum can be achieved by combining cyan, magenta and yellow coloured inks. In an ideal world, the CMY inks combined, would produce black; but because of impurities in the ink, the actual colour is a dark brown. This is why Black ink is used in addition to CMY.

CMYK separation plates

The photographs above show what the individual printing plates for cyan, magenta, yellow and black would look like when printed separately on white paper, and the large photo shows how the 4 CMYK separations combine to produce a final printed full colour image.