What is stored, and by whom
The camera writes the technical record: model, lens, exposure settings, orientation and the capture timestamp. Phones add a device identifier and, if location services are enabled for the camera, latitude and longitude accurate to a few metres.
Editing software then layers on its own tags — an XMP block describing the edit history, an IPTC block with author and copyright fields, and often a plain-text comment naming the application. A single photo can easily carry several kilobytes of this.
- GPS latitude, longitude and altitude — the precise spot the photo was taken
- Capture timestamp to the second, and sometimes the time zone
- Camera make, model and body serial number
- Lens model and the exposure settings used
- Software name, editing history and author or copyright fields