On Jan 6, 2020, at 7:20 PM, Roger Breton via colorsync-users <colorsync-users@lists.apple.com> wrote:
David,
It comes back to my "idea" of "threshold"; what's the 'criteria' that makes two colors appear "different" to a 'normal observer'?
An agreed upon deltaE value (and a formula for that deltaE report). The distance (difference) between two colors. I don't believe there's much debate that a dE value far below dE of 1, as I provided for the two sRGB values, are a far smaller color difference the human eye can see. There is some debate for good reason what values appear differently between two colors. From our friends at Chromix: http://www.colorwiki.com/wiki/Delta_E:_The_Color_Difference <http://www.colorwiki.com/wiki/Delta_E:_The_Color_Difference> And while I love the Chromix products, if you want a tool that really shows this off well, visually and numerically, BableColor CT&A is the cat's meow. Andrew Rodney http://www.digitaldog.net/ <http://www.digitaldog.net/>