These days there are really only two choices for full, RGB-color 3D printing: MCOR’s Iris paper-powered machine and 3D Systems’ ProJet x60 series of powder process 3D printers. The rest of the manufacturers are stuck with what one might call “Spot Color”, where specific portions of the model have specific colors.
In the current Stratasys Connex coloration model, a 3D model is subdivided into a collection of independent “shells”, each of which is a solid, watertight object on it’s own. They just happen to be adjacent to each other to form the complete model. Then their software permits you to select a color from a Connex3 color palette.
This style of color is useful for many applications, but not for complex color patterns and textures, many of which can mimic real life and provide a much more realistic-looking print.
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