Canon EOS-1D X Af Setting Manualbook page 33

single AF point
[4 surrounding points] and [8 surrounding points] options can be selected, based on
Hints and tips
the predictability of anticipated subject movement
The larger AF Area covered by [8 surrounding points] makes it an excellent choice to keep AF upon a
subject that will move quickly and erratically. For more predictable movement, the [4 surrounding
points] option still provides a compositional safety net, as well as helping with subjects lacking detail.
The expanded AF Area means more chances to not only keep AF upon your subject, but upon a detailed part of
the subject. The larger [8 surrounding points] AF Area is especially useful with subjects that you expect may
move erratically as you focus-track with AI Servo AF.
the primary AF point, even at the outermost
areas of the AF array — allowing great flexibility
in composition of action subjects. The larger,
expanded AF area makes it easier to keep AF
upon fast and erratically moving subjects.
In addition, when the subject has a lot of
movement, setting Case 5 or Case 6 from the
AF Configuration Tool is also recommended.
This will speed up the process of switching from
the primary AF point to an outer one.
Blue color of focus point is for illustration.
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