The defringe module leaves a black (instead of blue) fringe which is almost as visible as the blue one (almost no matter what I adjust). But as I told, I'm interested in general opinions about my idea and not a solution for my particular picture, since I will find it myself if I need it (up to now there were no complaints, so I will not reprocess it unless I try something from this thread to learn darktable).
I checked the original raw in different converters/viewers and I was wrong with my first analysis: The color fringe is in the original image data, so it may be “real” CA from the lens. It only occurs at one high contrast edge in the image with brown rocks on the left and fully blown-out sky on the right. The fringe is a couple of pixels wide. Shot with Canon EF 24-105 f/4 L IS on an EOS 400D crop camera. It is not my picture, so unfortunately I cannot share it. I only had to post-process it. With the CA module, the fringe changes color: blue -> psychidelic mixture, and this color mix fringe becomes visible on lower contrast edges as well when I toggle the module. The lens correction module was able to solve the problem, but introduced new problems somewhere else in the picture, as already described. I never had problems with the CA module with my own pictures, even with the same lens as above on crop and FF sensors. Best regards Chris Am 16.07.2015 um 13:23 schrieb johannes hanika: > did you try the defringe module? > http://www.darktable.org/usermanual/ch03s04s04.html.php#defringe > > cheers, > jo > > On Thu, Jul 16, 2015 at 11:41 AM, Christian Mandel <c.man...@gmx.net> wrote: > >> Hi! >> >> I was working on a picture showing a strong (blue) CA effect (I guess >> due to previous editing steps), but only on one edge inside the image. A >> "reflected" edge shows no such effect. My first thought was to use the >> CA correction within the lens correction module. It works perfect on the >> affected edge, but introduces a (red) CA effect on the reflected edge. >> That was the point where I discovered that the lens correction module >> has no mask. For the picture deformations that makes perfect sense, but >> IMHO not for CA correction. For the particular image I think I can get >> rid of the color fringe with different tools, but I would like to read >> your opinion on this topic: would it make sense to introduce a mask for >> the lens correction module (even if it does only affect the CA >> correction) or to move CA correction into its own module with a mask? >> >> Thanks & best regards >> >> Chris >> >> >> >> ------------------------------------------------------------------------------ >> Don't Limit Your Business. Reach for the Cloud. >> GigeNET's Cloud Solutions provide you with the tools and support that >> you need to offload your IT needs and focus on growing your business. >> Configured For All Businesses. Start Your Cloud Today. >> https://www.gigenetcloud.com/ >> _______________________________________________ >> Darktable-users mailing list >> Darktable-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/darktable-users >> > > > > ------------------------------------------------------------------------------ > Don't Limit Your Business. Reach for the Cloud. > GigeNET's Cloud Solutions provide you with the tools and support that > you need to offload your IT needs and focus on growing your business. > Configured For All Businesses. Start Your Cloud Today. > https://www.gigenetcloud.com/ > > > > _______________________________________________ > Darktable-users mailing list > Darktable-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/darktable-users > ------------------------------------------------------------------------------ Don't Limit Your Business. Reach for the Cloud. GigeNET's Cloud Solutions provide you with the tools and support that you need to offload your IT needs and focus on growing your business. Configured For All Businesses. Start Your Cloud Today. https://www.gigenetcloud.com/ _______________________________________________ Darktable-users mailing list Darktable-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/darktable-users
