Canon EOS-1D C Instruction Manual page 44

Attaching and Detaching a Lens
Minimizing Dust
When changing lenses, do it quickly in a place with minimal dust.
When storing the camera without a lens attached, be sure to attach the
body cap to the camera.
Remove dust on the body cap before attaching it.
Detaching the Lens
44
While pressing the lens release
button, turn the lens as shown by
the arrow.
Turn the lens until it stops, then
detach it.
Attach the rear lens cap to the
detached lens.