On Thu, 25 Apr 2013 16:07:13 -0400
Ed Huntress wrote:

snip
One thing I could use, though, is conversion back and forth to a
really broad colorspace that has a lightness (black and white)
channel. I used L,a,b with Photoshop. You get superior results with
unsharp masking by working only on the lightness channel (it avoids
color artifacts), and there are other things I like to do with it.

I'm not familiar with this (but learning). See if this blog entry
helps:

"...One of the hidden secrets of Gimp is that it supports the LAB color
space so you can get access to the L, a and b channels in an image.
This adjustment therefore produces similar results to those you can
achieve with my earlier post using Photoshop its just that the process
in Gimp is a little different..."

http://digital-photography-school.co...to-wow-in-gimp


--
Leon Fisk
Grand Rapids MI/Zone 5b
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