hoakley Macs, Technology

Q&A: EXIF missing data

Q If I use the shell command mdls to display the metadata for my photos, it does not include some EXIF fields which are shown when I inspect them in Preview or Graphic Converter. The missing fields include Destination Bearing Reference and Image Direction Reference. Why not?

The shell command mdls gives a brief list of EXIF-derived metadata.
The shell command mdls gives a brief list of EXIF-derived metadata.

A You are correct, and it is not obvious why the shell command mdls does not give the full EXIF fields. However even Preview shows but a small selection of them: if you open an image using Graphic Converter and glance at the huge list yielded by its EXIF tool, you will see many fields which do not appear in other apps.

Preview gives full location info and additional details, but not all EXIF metadata.
Preview gives full location info and additional details, but not all EXIF metadata.
Graphic Converter provides a huge list of EXIF metadata.
Graphic Converter provides a huge list of EXIF metadata.

One possible explanation is that mdls is actually part of the tools to support Spotlight, and only sees those metadata fields which Spotlight will index, which apparently does not include most of what is stored in the full EXIF metadata.