Precise masking along an edge?

pdvpjepj · December 30, 2020, 3:31am

I am new to Darktable coming from Capture One and still trying to figure things out. One thing I am confused about is whether it’s possible to draw mask along an edge of an element, for example the horizon. In the attached image I am trying to get a mask only for the sky but so far I am failing. I have tried to draw one with the brush (also with feathering) or a parametric mask but nothing seems to work properly.

How do more experienced users deal with this? Just use GIMP or can darktable do it?

2020-12-13-X-T3-DSCF2026.RAF (27.4 MB)

priort · December 30, 2020, 3:44am

Good enough??

priort · December 30, 2020, 3:50am

That is a drawn and parametric with a very quick parametric mask on the L channel only so it could be much more highly refined…also you can tweak opacity feathering blur and contrast to your liking…all could be used it this is not precise enough…2020-12-13-X-T3-DSCF2026.RAF.xmp (4.6 KB) You can start the parametric mask using the autopicker and then tweak the sliders to adjust the area affected. THere are lots of videos on masks but Mel did one recently and he explains it a bit…might help https://www.youtube.com/watch?v=3tEezKrVfXQ

pdvpjepj · December 30, 2020, 3:51am

Nice! It will take me a while to understand what you did :-(. But I am glad it’s possible. seems Darktable forces you get a better understanding of how digital photography works compared to tools like Lightroom or Capture One where it’s easier to get decent results quickly.

priort · December 30, 2020, 3:51am

Watch this …it will take you only 8 minutes to get it…or you can keep asking questions til you do get it…NP https://www.youtube.com/watch?v=3tEezKrVfXQ

pdvpjepj · December 30, 2020, 3:52am

I actually watched this video when I started out but I guess I didn’t get the subtleties first time around.

priort · December 30, 2020, 3:57am

Its the price of total control but once you get the hang of things and if you know a little bit of color theory you can get a lot out of it…Oh by the way welcome to the forum…If you don’t add the drawn mask then this quick parametric mask will be in other parts of the image…so this is one of the basic ways to mask…

priort · December 31, 2020, 5:24am

You could try to post this on the playraw section and have other edit it and you can look at the way they approach it…it seems like you are fine with that …the correct way is to append this to your post when you offer up an image… This file is licensed Creative Commons, By-Attribution, Share-Alike. If you add that I have a quick edit I could share but I should not do so until you explicitly provide permission…just FYI

Thomas_Do · January 1, 2021, 7:09pm

There is only very little contrast between sky and water. So, I would draw a straight mask for the horizon and exclude the rock by adding a parametric mask. Plus some feathering to get a soft transition.