Canon EOS 5D Mark II - EOS 5D Mark II 21.1MP Full Frame CMOS Digital SLR..., Service Manual

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General Information
21
7．Autofocus
7-1 Type:
TTL-CT-SIR AF-dedicated CMOS sensor
7-2 AF points:
9 AF points (plus 6 invisible Assist AF points)
⑴ Center AF point is vertical line-sensitive to f/2.8 and
sensitive to vertical and horizontal lines to f/5.6 as a cross-
type sensor.
⑵ The AF points above and below the center AF point include
six invisible AF points (two of them are vertical line-sensitive
to f/2.8). These invisible AF points function only in the AI
SERVO AF mode during automatic AF point selection and in
the AI SERVO AF mode with C.Fn-17-1 (AF point activation
area) and the center AF point selected. (It does not function
in the One-Shot AF mode.)
7-3 Focusing modes: 1) Autofocus
Other than the Full Auto mode, the following three AF modes
are user selectable.
[One-Shot AF]
When focus is achieved, the AF operation stops and locks (AF
lock).
⑴ AF-priority (The shutter can be released only when focus
is achieved.)
⑵ During evaluative metering, AE lock is set when focus is
achieved.
⑶ In metering modes other than evaluative metering,
exposure metering continues in real-time until the shutter
is released.
⑷ With applicable USM lenses, electronic ring manual
focusing can be used after focus is achieved with One-Shot
AF or if focus cannot be achieved with One-Shot AF.
[Predictive AI Servo AF]
Tracks subject movement and focuses continuously until the
start of exposure.
⑴ 1st shot during SW-1 ON: Shutter-release priority (shutter
releases after the lens drive stops during focusing).
⑵ 2nd shot onward during continuous shooting: Shutter
releases after the lens drive stops during subject tracking.
⑶ No focus confirmation light and no beeper.
⑷ If focusing is impossible, the focus confirmation icon
blinks.
[AI Focus AF (Automatic switching between One-Shot/
Predictive AI Servo AF)]
When the AF point which achieved focus in the One-Shot AF
mode detects subject movement, the AI Servo AF mode takes
over.
⑴ Automatically set in Full Auto mode.
⑵ In the AI SERVO AF mode, the beeper sounds.