Silly CIELAB questions

General Color & Graphics Printer Calibration & Profiling
1

Hey-ho–

I am trying to understand some apparently minor points about CIELAB.

Like:

What do the asterisks in CIELab* stand for? Do they represent a math function? (Not my best subject, although with explanations I can do.)

On the X-rite CIELAB color chart what is the significance of the 60, 60, -60, -60 clockwise around the circumference of the chart? I realize the grid in the chart is in increments of 2 from 0 out to 60 or -60 but what do the numbers signify? If it is just the chroma, how does the range 0 to 60 relate?

What value is considered the 0 point in the hue? It seems to be a red. Or does this even matter?

What is the best visual 3D diagram of the CIELAB sphere and where can I find it?

If I am allowed I would gladly post an image of the CIELAB chart I am talking about.

Thank-you for your indulgence and time.

2

The asterisks are to differentiate CIELab* from the Hunter Lab color space, which is calculated differently, and represent no math function.

3

It would be great if you could post an image of what you’re looking at so we could all see it. Instructions on posting images is here:

http://www.colorforums.com/faq.php#24

You just need to link to your image on a publicly accessible web server, wrap it on either end with the BBC codes
( ) and the ColorForum site will display the image within the thread.