"It looks like EXIF:SubjectDistance doesn't return a value."
The Metadata panel displays what's in EXIF:SubjectDistance, so if that's not present, LR won't display anything. I'm not sure why older photos from the D200 would have that field but newer ones not -- perhaps a firmware update at some point?
"I'm not sure of the accuracy of MakerNotes:FocusDistance. I don't think the bird in the picture was 7.94 meters (26 feet) away from me. It was more like 15 feet away."
I think the focus distan
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