A) Its not that I prefer Darktable, but it enables me to batch make images with their file name as watermark, a feature I have not been able to imitate in rawTherapee
If anyone knows a Linux way to do that outside Darktable, I’m all ears
B) Running ubuntuStudio 20.04 I have access to more tools than I know how to use
If it ends up not being a problem that can be fixed, to the benefit of all D3100 shooters, changing Darktable, I thought of a similar work around, but that would be more cumbersome, and only fix my problem…
[Note that Nikon doesn’t learn from their mistakes, and a similar problem happened 2 years earlier with an older version of Nikon Transfer and the D5000 (read here), and the new Nikon NX-D software has other corruption issues. The moral is: Don’t use Nikon Transfer or any other utility that modifies the file to download your precious images!]
It is very sad that this Nikon software bug penalizes only loyal Nikon owners (since it affects only people who had an older copy of the Nikon software from a previous camera), yet Nikon customer support provides no help other than suggesting that you contact your memory card manufacturer to see if the original images can be restored.
I tried it on the OP’s file and it didn’t create a fixed file using either 12 or 14 as input. It did create a fixed folder but the folder was empty, so I wasn’t able to test that a fixed file would subsequently open in DT.
ViewNX definately changes NEF files, but I don’t think the resulting files are corrupted. ViewNX reads them just fine (as do lots of other software packages). I think that from Nikon’s point of view the ‘MM’ variant NEF files are valid NEF files. Its just that most software that reads NEF files is based on reverse engineering camera files because Nikon have not released the NEF file specification.
You can also recover the files by passing them through Adobe DNG convertor (not free software though).
In terms of “proprietariness”, DNG is more open-source-friendly than the individual camera manafacturers’ raw formats. If more cameras encoded their raws as DNG, I think it would be quite popular…
All the raw converter software that uses the FOSS libraw library to open raws gets fundamental DNG support without even noticing it. My hack software does, but where I’d draw the line is in using all that DNG-included lookup table stuff to do default processing. Not a FOSS thing per-se, just an old fool being curmudgeonly…