Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 393)

AF Microadjustment
Adjusting for All Lenses by the Same Amount
Adjusting for Individual Lenses
Clearing All AF Microadjustments
Fine adjustment of the point of focus is possible when autofocusing in viewfinder shooting.
Before adjustment, also refer to
Precautions for AF Microadjustment and Notes for AF
Microadjustment .
Caution
Normally there is no need to adjust the position of focus. Perform this
adjustment only if necessary. Make sure to note that performing this
adjustment may prevent accurate focusing from being achieved.
Adjusting for All Lenses by the Same Amount
Keep adjusting, shooting, and checking the results to set the adjustment amount manually.
During AF, regardless of the lens used, the point of focus will always be shifted by the
adjustment amount.
1.
Select [ : AF Microadjustment].
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