> > What is a proprietary color _model_? What counts for an open one, exactly?
Hi Alex, This is a profound question, and I have to admit I struggled with the formulation of the text. Colour models cannot be proprietary, but colour systems can. The advantage of the CIE LAB and especially the CIE HLC fans is that they don't even pretend to be a colour system. Instead, they simply use the open and flexible CIE standard, which makes proprietary colour systems like Pantone superfluous. HTH, Christoph
