Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 303)

Silent Shutter Function
Disables shutter release sounds, operating sounds, and firing and illumination of the flash
and other light sources.
The following settings are used and cannot be changed.
Shutter mode: [ Electronic ]
Shutter release sound, focused beep: only headphone output
Touch sounds, self-timer sounds: silent
Shutter at shutdown: open
Long exposure noise reduction: [
Disable ]
Flash firing: [ Disable ]
AF-assist beam firing: [ Disable ]
Self-timer lamp: not illuminated
When using lenses equipped with focus preset, consider turning off the focus preset beep.
1.
Select [ : Silent shutter function].
2.
Select [On].
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