Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 210)

Note
General notes for lens aberration correction
Effects of lens aberration correction vary by lens and shooting conditions. Also, the
effect may be difficult to discern depending on the lens used, shooting conditions,
etc.
If the correction is difficult to discern, magnifying and checking the image after
shooting is recommended.
Corrections are applied even when an extender or life-size converter is attached.
If the correction data for the attached lens is not registered to the camera, the result
will be the same as when the correction is set to [
Disable ] (except for diffraction
correction).
If necessary, refer to the EOS Utility Instruction Manual as well.
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