CMYK or RGB for print: what Australian printers accept

In Australia. Australian trade printers commonly convert RGB themselves. Some overseas online printers insist on CMYK, so check the printer's own file requirements before you upload.

Colour settings for print

Screens	RGB
Printing presses	CMYK
Our print files	RGB, which Australian printers convert
Colour values in our guidelines	HEX, RGB, CMYK
CMYK conversion	a starting point for your printer, not a colour-managed match

Screens mix light and presses mix ink, so every printed colour goes through a conversion somewhere. This is where it happens and what it does.

What is the difference between RGB and CMYK?

RGB mixes red, green and blue light and is how screens make colour, while CMYK mixes cyan, magenta, yellow and black ink and is how a printing press makes it. A monitor can show colours that ink on paper cannot reach.

Should you send RGB or CMYK to an Australian printer?

Send RGB unless the printer asks for CMYK, because most Australian trade printers convert RGB in their own workflow with profiles set up for their press and paper. If a printer does ask for CMYK, tell them the file is RGB and let them convert it; they know their press better than a generic conversion does.

Our print files are RGB for that reason, and the README in every download that contains print files says so.

Why do colours change when they are printed?

Because the brightest screen colours sit outside what CMYK ink can reproduce, so the press prints the nearest colour it can. Bright blues and vivid greens shift most. Uncoated paper also absorbs ink and prints darker and softer than coated stock.

How does an RGB colour convert to CMYK?

The simple conversion takes the darkest share of the colour as black, then works out cyan, magenta and yellow from what is left. It is the arithmetic our guidelines document uses to state a CMYK value beside every brand colour, and here it is applied to the Café Kit's default palette.

The accent #FAF5EC converts to C0 M2 Y6 K2. A printer's colour-managed conversion will give different figures, which is why we state ours as a starting point for a proof rather than a match.

When do you need a spot colour?

When one exact colour has to match across many print runs, printers, or materials, such as a brand colour printed on signage, uniforms and packaging. Spot inks cost more per run, so a single order of cards is rarely worth it.

What about black?

Large areas of black print better as rich black, a mix of all four inks that your printer will set to suit their press. Small black text should stay black ink only, because a four-colour mix on small type shows colour fringes where the plates do not line up exactly.

Common questions

Do Australian printers accept RGB files?

Most trade printers do, and convert them to CMYK in their own workflow. Check your printer's file requirements, and if they ask for CMYK, tell them the file is RGB and let them convert it.

Why does my logo look duller when printed?

Screens can show colours that CMYK ink cannot reach, so the press prints the nearest colour it can. Saturated blues and greens are the usual casualties, and uncoated paper softens colour further.

Is the CMYK value in my brand guidelines exact?

No. It is a plain conversion from your RGB colour and a starting point for your printer. Ask for a proof before a long run if the colour matters.

Should I convert my file to CMYK myself?

Usually not. A printer's conversion uses profiles for their press and paper, which a generic conversion in a design program does not know about.