3Custom Function SettingsN

C.Fn III: Auto focus/DriveC.Fn-6 AF-assist beam firing

The AF-assist beam can be emitted by the camera’s built-in flash or by the external, EOS-dedicated Speedlite.



AF-assist beam 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 emit 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-6-0/2 is set.

C.Fn-7 AF during Live View shooting

When 1 or 2 is set, AF will be possible during Live View shooting. For details, see pages 102 - 106.


1:Quick mode (p.102)

2:Live mode (p.104)

C.Fn-8 Mirror lockup



Prevents camera vibrations caused by the reflex mirror action which can disturb shooting with super telephoto lenses or close-up (macro) shooting. See page 94 for the mirror lockup procedure.