Glossary
Maker note
The maker note is a proprietary, largely undocumented section of an EXIF block in which a camera manufacturer records whatever it likes.
Updated
Also written: MakerNote.
EXIF reserves one tag for manufacturers to fill with their own data in their own format. What goes in there is vendor-specific and mostly undocumented, but it is commonly the richest part of the whole block: body serial number, lens serial number, shutter actuation count, focus point data, in-camera processing settings.
The serial number is the field with real privacy weight. It is stable across every photo a given camera has ever taken, which makes it an identifier linking otherwise unconnected images and, by extension, otherwise unconnected accounts.
Maker notes are also fragile. They frequently contain internal byte offsets pointing into the surrounding file, so editing EXIF in place can corrupt them. That is why rebuilding a minimal EXIF block is safer than surgically rewriting the original — a point that matters when only the orientation tag is being preserved.
Related terms
- EXIF — EXIF is the metadata standard cameras use to record how, when and where a photo was taken, stored inside the image file itself.
- IFD — An Image File Directory is the table structure EXIF uses to store tags, inherited from the TIFF specification.
- Lossless — Lossless means the image data comes out bit-for-bit identical to what went in.