The EXIF data format has provision for camera manufacturers to include proprietary information in addition to the standard EXIF information. This information is contained in an EXIF field called the Maker Note field.

Each camera manufacturer chooses its own format for the Maker Note field, and they do not always publish this format. Through experimentation, individuals on the Internet have "reverse engineered" many of the formats used. All Maker Note information provided by the EXIFutils is based on these "unofficial" specifications, and therefore the correctness of this information cannot be guaranteed.

The EXIFutils provides partial or full interpretation of the Maker Note information for the following cameras makes:

• Canon
• Casio
• Epson
• Fujifilm
• Konica Minolta
• Nikon
• Olympus
• Panasonic
• Pentax
• Ricoh
• Sony