Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 657)

Shutter at Shutdown
You can set whether to leave the shutter open or close it when the camera's power switch is
set from <
> to < >.
1.
Select [ : Shutter at shutdown].
2.
Select an option.
: Closed
Closes the shutter. Normally set to closed, to prevent dust from
adhering to the sensor when you switch lenses.
: Open
Leaves the shutter open. This keeps camera quieter when the power
switch is set to <
> or < >. Useful when you want to shoot
quietly.
Note
Regardless of the setting, the shutter remains as it is when auto power off is
activated.
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