[cairo] Spot colors (and CMYK)

[Jon Cruz]

On Jan 21, 2010, at 9:15 AM, Bill Spitzak wrote:

> If Pantone colors come with a CMYK "alternative", this is an 
> approximation already! I see no problem with further approximating it by 
> the simplistic conversion (r=1-c-b, etc in sRGB gamma space). The 
> advantage is that this is pretty much reversable (perfectly reversble if 
> the value for b is known). Not only that I would not be suprised if 50% 
> of those "approximations" were done by choosing the values so that this 
> simplistic conversion of sRGB produced the best screen result!

Actually the pantone CMYK "alternatives" are quite an ugly mess, and not nearly sRGB based.

Instead they were based on physical efforts to create close results... *however* they are not common CMYK.

Instead they are very custom. In order to get closer to their ink values, Pantone had set up those samples to print inks in custom orders with custom screening that is not compatible with the norms used by print houses running CMYK.