Reviving an old topic to see if anyone has a new solution. In my short time working in the Micro 4/3 format, I've really enjoyed shooting with several legacy Nikkors and a nice Leica Summicron-C. Unfortunately, adapted lenses do not push any focal length or aperture setting info to the camera bodies and therefore, the resultant files are saved without EXIF data for these fields. I have succeeded in modifying the EXIF data file-by-file, tedious as it is, by using freeware such as Exif Pilot, which uses the open source software Exif Tool. Other no-cost solutions are available as well, some better than others. The trouble is that a trigger happy tog like myself can rack up many frames in even a short outing, which leads to hours of tedious modification of the EXIF data when forced to do them one at a time. I know there are solutions for batch-editing filenames to match timestamps as well as imposing GPS coordinates to a batch of files all at once. There are also ways to impose the entire set of EXIF data from one file to a batch of others. Both of these are a step in the right direction, but not exactly what I am looking for. It would be nice to modify just the focal length and max aperture of a batch of files without changing the other data, then come back through one-by-one to modify the actual f-stop file-by-file if desired. Any ideas?