Exif Tab

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The "Metadata" tab lets you control which Exif metadata will be contained in the saved (developed) image file. The Exif metadata is usually created by the camera itself and implemented into the raw image file. Basic Exif information is directly visible. Extended Exif information and so-called makernote data is organized into a tree. Click on the arrow at the very left of the desired sub-tree and you'll see its contents.

You can "Remove", "Keep", or "Add/Edit" Exif metadata. Manipulating metadata does not change the source file in any way! If you want to restore a value you have changed or removed by accident, simply press "Reset". "Reset All" works similarly but is used for trees and works recursively, which means that all values changed/removed in this sub-tree are restored.

You can "Add/Edit" the following Exif information:

  • Artist
  • Copyright
  • ImageDescription
  • Exif.UserComment

Only the English names of the Exif fields are displayed for easy reference. They are not translated when you choose a different GUI language.

Technical Details

Reading Exif.UserComment:

  • ASCII values are read without problems.
  • For Unicode values, RT detects if the string has an odd length.
    • If so, it's assumed to be a UTF-8 string.
    • If not, it tries to detect if a UCS-2 byte order mark (BOM) is set.
    • If no BOM is provided, and the string is a valid UTF-8 string, it tries to auto-detect the byte order based on the "zeros" count.
    • If it is not a UTF-8 string, it is assumed to be a UCS-2 string with the platform's byte order.
  • For undefined values, RT tries to convert the string from the local charset to UTF-8.

Saving Exif.UserComment:

  • If the string is pure ASCII, it is saved as ASCII.
  • Otherwise the string is converted to UTF-16 and saved without a byte order mark, using the metadata's byte order.