Canon EOS-1DX Af Setting Manualbook page 92

The [AF2] and [AF3] tabs include settings related to AF
operation parameters and shutter-release timing. With
these items it is possible to set which has priority (or a
balance) between focusing with AF, and the shutter-
release.
The [AF2] tab contains the [AI Servo 1st image priority]
and [AI Servo 2nd image priority] parameters for AI Servo
AF. The priority on focus and shutter-release can be set
for both the 1st image and subsequent images during
continuous shooting. With [Focus priority], shooting is
delayed until after the camera has focus on a subject
(this could be just a few milliseconds). With [Release
priority/Shooting speed priority] shooting takes place
instantly without waiting to focus, resulting in possible
out of focus images. The default [Balance priority] sets
equal priority on both (attempting to focus without
major delays to shutter release timings), ideal for most
s h o o t i n g s i t u a t i o n s . To m a k e u s e o f l o w - l i g h t
performance improved by the firmware upgrade during
continuous shooting, set the [During continuous
shooting] parameter to [Focus priority: +2].
When using One Shot AF the shooting priority can also
be altered via the [One-Shot AF release priority] option in
the [AF3] tab. The priority of focusing and shutter-release
can be altered in the same way as about during AI servo
AF. However there is no [Balance priority], and instead
[Focus priority] is the default setting.
92