I just give up using Lightroom.
Because I had to reinstall my system after Christmas, so I choose to try and install Manjaro along with the OEM Windows10. Taking this opportunity, I spent some time transfered all my photo collections from Lightroom 6 to Darktable.
The darktable used Lensfun library to perform lens correction. Lensfun have collected a lot of lens and camera data. By now (2020-02-28) there’re 1057 lenses in the database, and all the popular cameras are covered. The coverage can be checked here or in Lensfun project Github page. If the lens one use is not in the database now, one can choose to contribute to project by taking and uploading some photos to create calilbration data. There’s a good tutorial here.
I’m running the newest version of Darktable, and the version of Lensfun in my system (manjaro) is also newset. However, I can’t find my lens in the Lens Correction module, although it’s in the coverage list. According to this post and this one, it seems that we can update the local Lensfun database manually by the command
lensfun-update-data. No parameters are needed. If you want to update the database system-wide, you need to add
sudo before the command. After that, my lens appeared in the list.
— updated 17:36 March 2nd, 2020 —
If you’re using Windows, according to the answer provided by @sarunasb, you just need to:
xmlfile(s) containing tha cameras or lenses you need from Lensfun’s database, which has been moved to Github from Sourceforge.
Find the Lensfun database files installed in your system with Darktable, which could be
Update the correction files with the one you just downloaded. I.e., just copy downloaded
xmlto the local location in step 2 (e.g.,
C:\Program Files\darktable\share\lensfun\version_1), overwriting existing (needed to confirm admin access prompt).
Restarted darktable and the previosuly missing lens became available.