Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 357)

Shutter-Priority AE
[ ] recording mode enables you to set your preferred shutter speed for movies. ISO
speed and aperture values are set automatically to suit the brightness and obtain standard
exposure.
1.
Set the recording mode to [ ].
Turn the Mode dial to < Tv >.
2.
Set the shutter speed (1).
Set it by looking at the screen as you turn the < > dial.
The available shutter speeds vary depending on the frame rate.
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