Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 508)

For RF lenses with a focus mode switch
Set the lens's focus mode switch to < >.
2.
Magnify the image.
Each press of the < > button changes the magnification ratio, as
follows.
3.
Move the magnified area.
Use < > to move the magnified area into position for focusing.
To center the magnified area, press < > straight in.
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