Can anybody tell me if there's a plugin available that allows you to select by the color range?
e.g - highlights,shadows,midtones,etc. ?
I wrote a script http://www.silent9.com/incoming/scripts/select-colour-range.scm
to select be colour range. THe match my value or lightness might get what you want.
It was made to act similar to the photoshop select by colour function, but has no gui as it is script-fu.
Selects a region based on similarity to selected colour.
"Threshold" works like the Select by Colour Threshold slider.
"Fuzziness" determines the degree the selection is feathered into non-similar colours.
The idea is threshold defines the degree of similarity for 100% selected and fuzziness defines the spread of the selection into more dissimilar colours in the specified colourspace.