I’m glad, you like it @martin.scharnke 
- First I corrected the exposure in darktable without base curve and exported the image:
- Then in GIMP I extracted foreground with the help of foreground extraction tool and darkened background:
- In the next step I darkened the whole picture even more and with the help of dodge technique I only lightened certain areas around the monument a little bit.
By the way, I did not use GIMP tool dodge and burn, because with this tool brightened or darkened areas look very “washed out”.
It would be better if for the brush of this tool, blend modes and color could be set. Any GIMP developer here?
For dodging I used the usual method - new transparent layer with overlay blend mode and white brush with low opacity:
Note that the image is now very dark but this will change in the next steps.
- I converted the picture to black and white by desaturation module (Colours - Desaturate - Desaturate):
- Now is the time to give this clean look a little local contrast and restore the brightness of the image at the same time. One of the tone mapping algorithms, which is very often abused for HDR photos, is very suitable for this - Mantiuk 2006.
On duplicate of BW layer I applied (Colours - ToneMapping - Mantiuk 2006):
As you can see, this is too much, so the opacity of the layer should be very low to avoid the artifacts of the algorithm. In this case, around 14%:
Now we have emphasized the details and balanced the contrast of the image.
- Next step is to give the picture a vintage look. For this I used film emulation in G’MIC (G’MIC - film emulation - PictureFX - AnalogFX - Sepia Color 50% Strength):
- Last step was to emphasize that vintage look even more by adding some noise on duplicate layer (Filters - Noise - HSV Noise) Dulling = 5, Value= 0,5. After lowering opacity of that layer, merging down and final adjustment of contrast with curves result is:
