Re: CNS colors

David Perrell (
Thu, 08 Feb 1996 11:55:07 -0800

At 03:20 PM 2/7/96 +0000, Chris Lilley wrote:
>1) index -> Munsell colour.
> This is a widely used system for describing colour, and has been shown to
> perform well in usability studies.

Just curious as to where Munsell is widely used. The only reference I could find is in a book on color theory. Apparently Freehand includes the system, but it certainly isn't well-known in the graphics industry. I contacted a printer I've worked with for years who immigrated here from England. He was totally unfamiliar with Munsell, never had any color specified in terms of Munsell, and told me that in Europe, as in the US, Pantone reigns for spot color specification.

You make the point in another message that Pantone spot colors are not within the gamut of most RGB monitors. Is the Munsell spectrum?

>4) CIE XYZ -> RGB

Also curious as to practical difference between CIE L*a*b* and CIE XYZ. Did Adobe chose L*a*b* for some reason?

>5) gamma correction of RGB values
> This essentially boils down to
> a) am I on a Mac
> b) am I on an SGI
> c) am I on something else

I don't know about SGI, but newer Macs and DEC Alphas can use the same monitors and PCI-bus graphics boards as PCs. I read somewhere that QuickDraw has built-in gamma correction that can't be disabled. Is this true?

I recently purchased a rather inexpensive 15" color monitor for a client. The monitor has selectable white points, analog RGB adjustment, and color-correction software. Some video boards now include software for RGB and gamma adjustment. I wonder how incorporating white point and gamma in a color spec fits in with the long-term plans for universal color-management. I second Walter Ian Kaye's suggestion -- solicit input from cms reps early.

David Perrell
Hearn/Perrell Art Associates
Presentation graphics & animation
Photo retouch & enhancement
(1.818) 884.7151