As far as the colour quality of dye-sublimation goes, it outstrips that of conventional printing techniques. Dye sublimation doesn’t use the primary colours to generate all the other colors—it captures colors much like a chemical image does. You know how pictures produce the entire colour spectrum without any distortions? Dye sublimation does the same thing because sublimation inks or dyes use the same colours as present in the image you intend to print out.
Since the dye is trapped in transfer material fiber, there’s no risk of fading, and the final print is as close to the digital image as possible. Dye-sublimation creates the closest possible copy of the full vibrancy of colours as caught in your images. Additionally, the colour doesn’t fade, nor does it wash away—making dye sublimation a far better method of printing posters such that you capture the full depth and texture of the colors you intend to print.