Canon EOS-1DX Af Setting Manualbook page 7

Various settings for AF-related features
can be made with AF menus [AF2] - [AF5]
The [AF/2] tab includes settings related to cameras
priority concerning shutter-release timing when using AI
Servo AF. [AI Servo 1st image priority] and [AI Servo 2nd
image priority] make it possible to make focusing the
priority slowing the shutter-release timing, or prioritize
faster shutter-release.
Within the [AF3] tab, the [One-Shot AF release priority]
settings related to focusing and shutter-release timing
when using One-Shot AF release priority. The other
options [USM lens electronic MF] and [AF-assist beam
firing], control the manual focus operation of some
lenses and the operation of AF assist function of
attached Speedlites.
AF2 AI Servo
Settings related to the
camera priorities when
using AI Servo AF
AF3 One-Shot
Settings related to
focusing and
shutter-release timing
when using One-Shot
AF release priority
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