If you’ve used a professional printers before, chances are you’ve been asked to ensure your artwork is sent in CMYK, not RGB.
But what is the difference between the two colour palettes? And why do printers and designers create in CMYK? Here’s some insight into how CMYK works.
Intro To CMYK
As outlined in our Colour Support Guide, CMYK is the standard colour palette for commercial print documents. It is also the term for the four inks used; cyan, magenta, yellow and key (black.) At most print companies, the ink is typically added in the order designated by the abbreviation. Black’s abbreviation is K for “key” because the other colours are aligned, or keyed, with the black key plate.
CMYK v. RGB
There are some significant differences between CMYK and RGB colour palettes. While CMYK is the standard for print, RGB is the selection of colours used on computer displays.
CMYK uses a subtractive process to create colours; the canvas is white to begin with, and colours are layered on to block out part of the spectrum. The ink reduces the light that would otherwise be reflected. This is known as “subtractive” because the inks subtract brightness from the white background. By comparison, RGB colours are additive. That means they print on a canvas that’s black to begin with, and colours layered on top create the final image.
RGB uses a colour management system that mixes shades of red, green and blue in order to develop colour images. But because it’s different than CMYK, if artwork is designed in RGB, it may be altered when converted to CMYK for print. While converting colours from one palette to the other is possible with programs like Adobe Photoshop, there is no simple method for doing so. Therefore, colours are likely to change when a creation goes to print. For those who don’t want to risk colours appearing differently than intended, designing in CMYK from the start is recommended.
Printing with CMYK works in part through a process called halftoning, which allows less than the full saturation of primary colours. Tiny dots of colour are printed in a small enough pattern that they appear solid. For example, magenta with a 20% halftone produces pink, because the little dots on the white background seem lighter and less saturated than pure, bright magenta ink.
The Key Colour
There are several great reasons for black being the “key” colour in the CMYK palette. It plays an important role in the print process. Black serves as an outline and colour indicator; it also enables the designer to print text with fine details, without any slight blurring. Black is also essential as printing with only cyan, magenta and yellow would soak paper with ink, making the drying process slow and impractical. This can also cause the ink to bleed.
Furthermore, as black ink absorbs more light, it yields much better black tones than a combination of cyan, magenta and yellow. Black ink is also less expensive than the corresponding amounts of other inks.
CMYK is the preferred choice for designers and printers, despite RGB having a larger colour spectrum. The challenge is that colours are created in RGB which aren’t available in CMYK, such as vivid fluorescent shades. This results in those pesky colour conversion issues previously mentioned.
CMYK is also preferred because it achieves the best results. Colours are crisper and images more vivid as they are intended to go on a white surface, which is what most card stock is to begin with.
CMYK For Your Print
When it comes to designing your business cards or other print project, you may want to speak to our design team before submitting your own artwork. They can design your print for you, or offer advice on converting an existing file to CMYK. Another option is to use our Create Your Own Tool, which will ensure that your cards are print ready from the start.