Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 175)

Digital Tele-Converter
You can adjust the shooting magnification to be higher than the lens magnification.
1.
Select [ : Digital tele-conv].
2.
Select a shooting magnification.
Different shooting magnifications are available when [ :
Cropping/aspect ratio ] is set to [ 1.6x (crop) ].
Shooting magnification is not adjusted when [ Off ] is selected.
Note
One AF point is used, fixed at the center. Tracking frames are not
displayed.
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