At first step I thought I can take lens data for Nikon Z6 and add them to lensfun database manually to see as a test whether this will function. At the second step, I would take pictures and submit them to get the right and complete lens correction data incl. vignetting compensation.
When I encounter at the first step that difficulty of the unidentified lens, how can you be sure that at second step it will function?
Those lens data from Viltrox lens for Nikon are just numbers. How can we argument that those belong to a full frame camera and DT may not recognize as a consequence.
How do you think the rest of the data in the lensfun database got there? Do the procedure, submit the data, and the repo maintainers will make sure it gets to the proper place. With that, you won’t have to worry about XML formatting and content…
Even if you perform the calibration for the APS-C crop, the fallback string AF 85/1.8 II XF currently used by dt on the camera body in question will not be sufficient to identify this lens automatically.
Glenn, frankly I do not know what is missing in order the lense will be identified. The fact is DT does not identify the Viltrox lens automatically. I entered the data exiv2 delivered into .xml file of lensfun database as shown above.
I believe this would function. I am Windows user and DT runs under Windows. I could not find any reliable information what should be the contents of that file and where to locate in Windows system.
So the Fujifilm MakerNote doesn’t include the LensID/LensType numerical tag like e.g. Canon or Nikon do, so not sure how the exiv2.ini mapping would work in this case. I’ll have to take a closer look at the exiv2 and dt code when I find some time…
What’s interesting is that there is a lensfun crop entry for another Viltrox on the X-mount, which indeed also does not have the “Viltrox” prefix, so they will likely accept another entry like that (the existing one for the full crop and including the prefix being unsuitable and therefore completely different), so this is probably the best bet.
Not really. But someone else did, at least in part. There was an announcement here some time ago (1-2 years already maybe?) and an associated pr for darktable, that supported Fuji and Sony cameras. I integrated it into art and extended also to dng files (also not reverse engineered, just taken from the dng spec and adapted from the lcp implementation already available in rawtherapee). IIRC someone else also figured out part of the corrections for Panasonic cameras (or possibly even all m43 cameras), but I haven’t looked into that yet.