kc8ufv: You raise an interesting point. How much of the difference between two colors is objective (can be measured reproducibly) and how much is subjective (varying from person to person) perception? Color blindness is the canonical example of such disparity. From some of the comments on this thread (including perhaps my own) it would appear that folks do see these two pictures differently. And, of course, that implies that we see tartan differently, too.

I'm with The Barry preferring the purple hue. And, like you, I prefer the Maclean of Duart tartan on the right. It is brighter and the blue looks "blue", not "sky blue", at least to my eyes and on my monitor. :-)