Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 66)

Detaching a Lens
1.
While pressing the lens release button, turn the adapter as shown by
the arrow.
Turn the lens until it stops, then detach it.
2.
Detach the lens from the adapter.
Hold down the lens release lever on the adapter and turn the lens
counterclockwise.
Turn the lens until it stops, then detach it.
Attach lens caps to the lens you removed.
Caution
For lens precautions, see Attaching/Detaching RF Lenses .
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