Hi Justin,

IFD0 is one directory in the EXIF information. ExifTool does not zero this. You may be referring to the problem where some tags are duplicated between the ExifIFD and IFD0. ExifTool will remove the duplicate tag if it exists when you are writing that specific tag. However, no information is lost since this tag exists in another location (and it really shouldn't have been duplicated to begin with). I'm not sure that NEF images have this duplicated tag problem anyway.

I always recommend keeping backups of your originals, but there should be absolutely no information or image loss when editing NEF with exiftool.

- Phil