Hi there,
I to get a crisp 3D-like feeling to the image of the windsurfer and I feel it could be a tad better. I managed to get the white parts of the sail yellowish which I don’t like. Otherwise I’m relatively satisified. Would love to see some tweaks :).
Raw: DSC08810.ARW (23.8 MB)
XMP: DSC08810.ARW.xmp (6.0 KB)
This file is licensed Creative Commons, By-Attribution, Share-Alike.
You forgot to post your own result 
And the XMP doesn’t have your edit, just default settings.
The default white balance is on the yellow side, so that might be why.
Here’s my attempt:
Crispiness_wanted_DSC08810.ARW.xmp (26.5 KB)
Not 100% happy with it, but decent enough. Need to figure out how to best deal with the chromatic aberrations on the water.
I don’t have darktable, so played in the GIMP. Used layers and two masks. One mask made with the Threshold function, the other it’s inverse.
Before at left of course.
My take on it, ART 1.20.1.
Crop, very slight bit of chroma added to the sky through a gradient mask, foreground local contrast through a gradient mask, selected chroma boost here and there and that’s about it. Others may be better at this than I, but I found it kinda difficult to make it sharper / crisper without making it crunchy due to all the fine detail in the water spray and elsewhere. Ideally, I’d like to see the subject a little farther left in the frame to make it more compositionally dynamic, but that’s not really possible without severe cropping.
On a side note, I’m glad to see that half-subtle green stripe in the background water on some others’ versions. I thought it was something I had done inadvertently.
Here’s my version - nice shot!
Just my normal kind of workflow, with a fairly vigorous application of one of my own diffuse or sharpen presets, and a tiny bit of masked tone eq to lighten the person slightly.
Btw, @MPiX, which lens did you use? RawTherapee can’t seem to positively identify the lens and lists several possible alternatives. Asking since I’d like to apply the right lens corrections.
With RT 5.9
Edit: I changed the edition because I wanted to add some light to the surfer with the “Log Encoding” module.
Greetings!
Nice photo! I’m no expert, but it appears to me that your lens did a good job of capturing detail. Here’s my long, changed my mind a lot, version:
DSC08810_08.ARW.xmp (53.4 KB)
I forgot my own edit…here it is with yellow taken away (as suggested from Donatzsky) with colour zones. How do I find the xmp-file with my tweaks? I attached the xmp that is a sidecar to the original…obviously it was wrong!?
Another a bit lighter and sharpened.
Thanks for your edits. Some are really great and gave me good guidance. HoweverI have problems knowing when to stop haha 
An old Tamron 28-200… Didn’t find any corrections for it in DT. The a68 is my backup camera. Don’t want to use my A73 when shooting windsurfing. Too much sand and water blowing around.
You should be using color calibration, not color zones, for adjusting white balance. In this case, moving the temperature slider a little to the left is all that’s needed.
But I will say that color zones dealt very nicely with the purple fringing in the water.
Yeah that’s an issue I know all too well, and others have said similar things. I always try to implicitly force myself to leave well enough alone by calling edits “DSC_1234 FINALIZED”, but of course there’s always another edit called “FINALIZED2f GIMP_contrast_layers_4 local_color” 
