Canon C12-8453, Service Manual

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3) AI Focus AF: Switches between One-Shot AF and
Predictive AF/AI Servo AF automatically.
For a still subject: AF operation stops (AF lock) when focus is
achieved.
For a moving subject: Tracks subject movement continuously
up to the start of exposure.
* When a USM lens is used, manual focusing with the
electronic focusing ring is enabled after autofocus is achieved
with One-Shot AF or when focus fails to be achieved.
* AI Focus AF is set automatically in the Full Auto mode.
(2) Manual focusing
After the lens focus mode switch is set to MF (or M), manual focusing is
enabled with the focusing ring.
* During automatic focusing point selection, Focus Aid is provided for
the seven focusing points. During manual focusing point selection,
Focus Aid is provided for the selected focusing point. The in-focus
indicator <
●
> lights. The beeper will sound when enabled with the
Func. setting.
* When the shutter button is pressed halfway and metering is active,
the MF icon blinks at 2 Hz on the LCD panel.
2-4 Focusing methods: (1) Focusing point selection with Eye Control
Works in all picture-taking modes except Full Auto.
(2) Automatic focusing point selection
Set automatically in the Full Auto and Programmed Image Control
modes. Can be set manually in the Creative Zone modes.
* With the Eye Control switch turned ON in the Full Auto mode, the eye
position is detected automatically and this information is incorporated in
the automatic focusing point selection algorithm. It increases the chances
for the camera to select the focusing point that the user desires.
(3) Manual focusing point selection
Enabled in the Creative Zone modes.
* Not available in the Full Auto and Programmed Image Control modes.
2-5 Focusing point selection: (1) Eye Control
1) One-Shot AF
The eye selects the focusing point by looking at it in the
viewfinder while the shutter button is pressed halfway.
2) AI Servo AF
AF operation starts in the same way as with the One-Shot AF.
But while the shutter button is pressed halfway during
continuous shooting, the moving subject is tracked by the
focusing points which the eye looks at (Eye Control Servo).
3) AI Focus AF
The AF operation starts in the same way as with the One-Shot
AF. However, if the subject starts moving after focus is achieved
in the One-Shot AF mode, the camera switches automatically to
AI Servo AF. While the shutter button is pressed halfway during
continuous shooting, the moving subject is tracked by the
focusing points which the eye looks at (Eye Control Servo).
Part 1: General Information
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