The DNG (EXIF) tag Semantic Instance ID (p.71, 1.6.0.0 spec) seems to have been accidentally named Semantic Instance IFD in Exiftool? I have no idea why you would be thinking of IFDs. : )
(It is in Semantic Mask IFD. I'm probably wrong again, but my intentions are good...)
- J
Great, thanks! (sometimes my fingers have a mind of their own)
I'll fix this in 12.46
- Phil