Canon EOS 20D Digital, Service Manual

Page: 85 / 374

7) Automatic AF point selection
The automatic selection of the AF point in both the One-Shot AF and AI
SERVO AF modes is based on the same algorithm used by the EOS 10D. The
automatic AF point selection speed and AF point selection accuracy (matching
the user's intended subject) are also about the same as the EOS 10D's.
8) AF point selection
The AF point is manually selected with the Multi-controller on the camera
back.
The Multi-controller can be pressed in 8 directions as well as at the center.
After you press the AF point selection button, press the Multi-controller in the
direction of the AF point you want to select. Pressing the Multi-controller at the
center will select the center AF point. And if you press the Multi-controller in the
direction of the currently-selected AF point, automatic AF point selection will be
set (all the AF points will light).
You can also press the AF point selection button and then turn the Main Dial
or Quick Control Dial to select a AF point.
Also, if C.Fn-13-1/2 (AF point selection method) is set, you can skip pressing
the AF point selection button and just use the Multi-controller or Quick Control
Dial to select the AF point directly.
9) AF-assist light
As with the EOS 10D, the AF-assist
light is a series of stroboscopic flashes.
The working range is approx. 4 meters
at the center and approx. 3.5 meters at
the other 8 AF points. In the case of an
EOS-dedicated, external Speedlite, see
Table 006.
Technical Information
13
Multi-controller operation
Main Dial/Quick Control Dial operation
Automatic
AF point selection
Fig. 021 AF point selection sequence
Manual Selection
Diagonal
Left/
Right
Center
● ●
● ●
×
●
× ×
× ×
×
●
× ×
● ●
Table 006 AF-assist with External Speedlites
Automatic
Selection
Speedlite
Top/
Bottom
ST-E2
430EZ
540EZ
220EX
380EX
420EX
550EX
SL580EX
●
●
*
●
●
*
●
*
●
●
●
●
●
●
●
●
●
●
●
×
×
×
×
×
×
●
●
* Focus can be achieved only with the center AF point.