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Old July 12th, 2011, 07:46 AM
Andrew Rodney Andrew Rodney is offline
Join Date: May 2006
Posts: 467

Originally Posted by Doug Kerr View Post
[GMWAS: gag me with a spoon]
In one piece, they say:

Beyond RGB is similar in concept to the Lab color space, in that it is also a three dimensional space with brightness or luminance on one axis and color information on the other two.
That they lump brightness (not Lightness) and luminance in the same sentence as if they are the same is enough to warrant suspicion here!

From what I understand, the L in Lab is Lightness (a property of color). Brightness is a human perception, not the same. Luminance is the properly of an emissive surface or reflection from a surface (cd/m2).
Andrew Rodney
Author "Color Management for Photographers"
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