Hi Anthony, On http://www.imagemagick.org/Usage/photos/, you have a minor underexposure example.
Before going into -sigmoidal-contrast operator, maybe it is a good idea to first discuss convert's built-in -normalize operator that is similar to GIMP's "auto-levels" or "normalize" feature that stretch pixel values from darkest to brightest. convert minor.jpg -normalize minor.normalized.jpg Also, maybe you'd like to through in how IM can also create the three-color histogram out of it: convert minor.jpg histogram:- | convert - minor.histogram.jpg Looking at the histogram, I think it may explain what you wrote: __________________________ Sigmoidal contrast brightening tends to de-emphasize the red end of the spectrum. You may end up having to select a parameter that results in the most natural flesh tones, rather than the brightness level you really want. __________________________ -- Tong (remove underscore(s) to reply) http://xpt.sf.net/techdocs/ http://xpt.sf.net/tools/ _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
