Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 394)

2.
Select [All by same amount].
3.
Press the < > button.
4.
Make the adjustment.
Set the adjustment amount. The adjustment range is ±20 steps.
Setting it toward “–: ” will shift the point of focus in front of the
standard point of focus.
Setting it toward “+: ” will shift the point of focus to behind the
standard point of focus.
After making the adjustment, press < >.
Select [ All by same amount ], then press < >.
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