Canon EOS-1D X Mark II DSLR Camera (Body Only) - Manual (Page 290)

Focusing with AF (AF Method)
290
In the [ FlexiZone - Single ] mode, either
press the < u > button or tap on [ d ]
displayed on the bottom right of the
screen. You can magnify the image by
approx. 5x or 10x and check the focus.
To move the AF point, operate < 9 > or tap on the spot you want to
magnify.
Either press the < u > button or tap on [ d ] to magnify the image.
Each time you press the < u > button or tap on [ d ], the
magnification ratio changes.
At 100% (approx. 1x) magnification, operate < 9 > or tap on the
screen to move the magnifying frame. Pressing < 9 >, < 0 >, or
< L > button will return the magnifying frame to the screen center.
Either press the < u > button or tap on [ d ] to magnify the area
covered by the magnifying frame.
When the image is magnified by approx. 5x or 10x, you can change
the magnified area by operating <
9 > or tapping on the triangle on
the screen top, bottom, left, or right.
If you press the shutter button halfway, AF will be performed in the
magnified view.
If focusing is difficult in the magnified view, return to the normal view
and perform AF.
Magnified View for FlexiZone - Single
Magnified view is not possible with [ u +Tracking ].
If you perform AF in the normal view and then the view is magnified,
accurate focus may not be achieved.
AF speed differs between normal view and magnified view.
When in magnified view, Movie Servo AF (p.331) will not work.
In magnified view, images will be displayed without chromatic aberration
correction or distortion correction applied.
During magnified view, achieving focus becomes more difficult due to
camera shake. Using a tripod is recommended.