Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 212)

Caution
Some Speedlites cannot be attached directly to this camera. For details, see Multi-
Function Shoe .
Setting [ : Auto Lighting Optimizer ] ( ) to an option other than [ Disable ] may
still cause images to look bright even if you set lower flash exposure compensation
for darker images.
In flash photography, set [
: Shutter mode ] to an option other than [ Electronic ]
( ).
Note
The Speedlite will fire an intermittent AF-assist beam as needed, if autofocusing is
difficult under low light.
You can also set flash exposure compensation in [
Flash function settings ] in [ :
External Speedlite control ] ( ).
The camera can turn on certain Speedlites automatically when the camera is
turned on. For details, refer to the instruction manual of Speedlites that support this
feature.
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