Hi, I have a Sigma Lens which I do not find supported yet. Though the entry

cat ~/.exiv2
[nikon]
201=Sigma 24-70mm F2,8 DG OS HSM Art

is working fine I hope I can help others to have an automatic support. As described at 3. Contributing Lens Data I shot a small JPG with caps-on that is unmodified and attached to this case.

I would love to make a pr, but I have no idea and did not find any documentation how to create and interprete the data required for fmountlens[].

Btw, these links are dead (from src/nikonmn_int.cpp):
//------------------------------------------------------------------------------
//
//
// Created by Robert Rottmerhusen 2005 - 2018
// http://www.rottmerhusen.com ([email protected])
//
// For contributor info and more visit my online list:
// http://www.rottmerhusen.com/objektives/lensid/thirdparty.html

Kind regards
Dave