(Roland DGA. Full article here.)

The first thing I always look for is whether a CMYK or RGB color space was used to design the image. It was determined that CMYK was used, leading to a general discussion about CMYK vs. RGB color spaces and how important designing images in RGB can be. The reason for this is simple, there are a lot more colors (“Crayons”) in RGB than CMYK output. That being said, you cannot convert an image (vector or raster) from CMYK to RGB thinking that it will print more vibrant – you can't add colors to an image that's already limited in color (24 Crayons). My recommendation is to design your images in RGB color space (64 Crayons). I use “AdobeRGB-1998.”

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