In the meantime, you can try:http://www.sno.phy.queensu.ca/~phil/exiftool/
I have used it to play with a few D7100 images and it seems to work just fine in single file or *.NEF mode. You can also use Nikon's ViewNX2 to save 8/16 bit tiff files although I do not know what the conversion would do to your digital negative. I have not seen any issues with the exiftool above and published a few on my website. Hope this helps.