Knowledge Centre
Colour: CMYK, RGB & Spot
Screen colour and printed colour are different experiences.
RGB and CMYK
RGB describes colour made with light on a screen. CMYK describes process colour made with cyan, magenta, yellow and black in print. Conversion depends on colour management and the intended output; some bright screen colours cannot be reproduced the same way on paper.
Spot Colours
A spot colour is specified as a separate ink or production separation. A named spot swatch may instead be simulated on a process press, so confirm whether an actual spot ink is required and available. Special finishes also need agreed separations.
Agree the Reference
For colour-critical work, discuss the stock, output profile and appropriate proof. A phone display is not a reliable colour reference. Avoid converting files repeatedly or assuming that any generic CMYK setting suits every press.
Further Reading: helpx.adobe.com