Canon EOS RP Instruction Manual page 752

Custom Function Settings
C.Fn III-7: Release shutter without lens
You can specify whether shooting still photos or movies is possible without
a lens attached to the camera.
0: Disable
z
1: Enable
z
C.Fn III-8: Retract lens on power off
You can set whether to retract gear-type STM lenses (such as EF40mm
f/2.8 STM) automatically when the camera's power switch is set to < 2 >.
0: Enable
z
1: Disable
z
With auto power off, the lens will not retract regardless of the setting.
o
Before detaching the lens, make sure that it is retracted.
o
When [0: Enable] is set, this function takes effect regardless of the lens's
o
focus mode switch setting (AF or MF).
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