Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 119)

4.
Select [OK].
5.
Take the picture.
After you press the shutter button completely, the bulb exposure
continues for your specified time.
[ ] and the exposure time are displayed on the LCD panel
during bulb timer shooting.
To clear the timer setting, select [ Disable ] in step 2.
Caution
Bulb exposure stops if you press the shutter button completely and release it during
the timer.
Bulb exposure continues even after your specified exposure time if you keep
pressing the shutter button completely (which overrides automatic stopping when
your specified exposure time elapses).
The bulb timer is cleared (and reverts to [
Disable ]) when you switch shooting
modes.
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