Af Point Selection Method; Superimposed Display; Af-Assist Beam Firing - Canon EOS 50D Instruction Manual

C.Fn III -3
0: Normal
Press the <S> button and use <9> to select the AF point.
1: Multi-controller direct
Without pressing the <S> button first, you can just use <9> to select
the desired AF point. Pressing the <S> button will set it to automatic
AF point selection.
2: Quick Control Dial direct
Without pressing the <S> button first, you can just use the <5> to
select the desired AF point. By holding down the <S> button and
turning the <6> dial, you can set the exposure compensation.
C.Fn III -4
0: On
1: Off
When focus is achieved, the AF point will not flash in red in the
viewfinder. Recommended when it is bothersome to see it light up.
The AF point will still light when you select it.
C.Fn III -5
The AF-assist beam can be emitted by the camera's built-in flash or by the
external, EOS-dedicated Speedlite.
0: Enable
1: Disable
The AF-assist beam is not emitted.
2: Only external flash emits
If an external, EOS-dedicated Speedlite is attached, it will emit the AF-
assist beam when necessary. The camera's built-in flash will not fire the
AF-assist beam.
If the external, EOS-dedicated Speedlite's [AF-assist beam firing] Custom
Function is set to [Disabled], the Speedlite will not emit the AF-assist beam
even if the camera's C.Fn III -5-0/2 is set.

AF point selection method

Superimposed display

AF-assist beam firing

3 Custom Function SettingsN
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