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:) do you have any suggestions for a easy to use post-processing app for this kind of pics?
i use FastStone Viewer for quick editing but is quite limited for astro and also for normal stuff xD

i still have the raw of this one and would love to make it look better :D

Lightroom will do just about everything you need, but Gimp is free and can also work well. Many people like Darktable, but I do not have much experience with it. Darktable can work with raw images and many people say its comparable to Ligthroom.

Hope this helps
https://www.gimp.org/
https://www.darktable.org/

thx! seen some of your stuff and looks really nice :D
the desert astro shots are my favorite :D