SSelecting the AF PointN
Selecting with the Dial
Press the <S> button, then turn the <6> dial or <5> dial to select the AF point in the looping sequence shown on the left.
When looking at the LCD panel to select the AF point, note the following:
Automatic selection | , center | , right | , |
top | | | |
If focus cannot be achieved with an EOS-dedicated, external Speedlite’s AF-assist beam, select the center AF point.
About AF-Assist beam with the Built-in Flash
Under low-light conditions, when you press the shutter button halfway, the built-in flash fires a brief burst of flashes. It illuminates the subject to enable easier autofocusing.
In the <3> <5> <7> modes, the AF-assist beam does not light. The built-in flash’s AF-assist beam is effective up to about 4 meters/13.2 feet.
In the Creative Zone modes when you pop-up the built-in flash with the <I> button, the AF-assist beam will be fired when necessary.
Lens’ Maximum Aperture and AF Sensitivity
The EOS 30D’s AF sensor has nine AF points. The center AF point is a high-precision, cross-type sensor sensitive to both vertical and horizontal lines of the subject. The top and bottom AF points are vertical line-sensitive, and the remaining six AF points are horizontal line- sensitive AF points.
With f/2.8 and faster lenses,* the vertical line-sensitive sensor at the center AF point will also function to attain high-precision focusing.
*Except with the EF28-80mm f/2.8-4L USM and EF50mm f/2.5 Compact Macro lenses.