Yellow and Blue make green. Red and blue make Purple. Those lessons from kindergarten are the building blocks for the process that gets the colors from your design translated correctly to a tee-shirt or garment.
Each color that is in your design must be broken down into individual parts or components before it gets output to a screen. The process of isolating each color is commonly referred to as a “color separation.”
There are a few different techniques to do this, and below, we’re going to break down a few of the key processes commonly used:
Four color process printing is a printing process where you begin with finished full color artwork and separate out the artwork into the CMYK format – Cyan, Magenta, Yellow, and Black. The separate films are created and printed with special process inks and the print looks like the original artwork. Four color process lends itself well on white color garments.
Index printing is a process where a design with multiple colors is reduced down to a limited color palette. The process of “indexing” a design also converts the design to a diffusion dither random square dot (all the dots are the same size) pixel pattern rather than halftone dot patterns. The design is separated and printed directly from Photoshop, or the file is brought into a drawing program for additional text or graphic elements.
This term has been around for a long time. In simple terms, it is a method of printing photorealistic images without using the standard CMYK separations. This type of printing is used on Medium and Dark color garments to simulate four color process.