Anton, I can't remember all the details, but I think using a parametric mask based on hue can do this. You may want to combine this with a shaped mask to limit the area of the image impacted.
Regards, Tony. On Mon, 2017-01-16 at 10:30 -0500, Anton Aylward wrote: My Sony camera has a "picture" setting that produces an image that brings out one primary color and makes the rest of the scene B&W. You've probably seen this kind of effect in advertising. The downside of using this in-camera option is that it (a) only works for the 3 primary colours and (b) only works in JPG mode, not RAW. I prefer to use RAW and post-process since I can also do things like deal with skylines and shadows, so I wonder how I would do this in DT after I've done that basic processing. If this is a single discrete object such as a red sport scar in the midst of otherwise banal traffic, such a I've seen in adverts, then its easy enough to crop. But there are many situations where the colour you want is distributed, perhaps the green of trees on a street scene. As I say, this only works for primary colours. I can think of a few photographs I've got where I'd like to apply this technique but the color I want to bring out isn't primary. Other then simply killing the green and blue in a color profile, what can I do about the sport car scene? or red and blue in the trees in the street scene? -- Tony Arnold MBCS, CITP | Senior IT Security Analyst | Directorate of IT Services | G.110, Kilburn Building | The University of Manchester | Manchester M13 9PL | T: +44 161 275 6093 | M: +44 773 330 0039 ____________________________________________________________________________ darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.or
