Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 218)

Dust Delete Data Appending
The camera will append the Dust Delete Data obtained to all shots from now on. Acquiring
Dust Delete Data before shooting is recommended.
For details about using Digital Photo Professional (EOS software) to erase dust spots
automatically, refer to the Digital Photo Professional Instruction Manual.
File size is essentially unaffected by Dust Delete Data appended to images.
Caution
Dust Delete Data is not obtained when EF-S lenses are used, or when [ :
Cropping/aspect ratio ] is set to [ 1.6x (crop) ].
Dust Delete Data is not added to images when [ Distortion correction ] is set to
[ Enable ].
If the object has any pattern or design, it may be recognized as dust data and affect
the accuracy of the dust deletion with the Digital Photo Professional (EOS
software).
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