Canon EOS R50 Mirrorless Camera (White) - Manual (Page 506)

3.
Change the orientation information.
As you watch the camera and icon in the upper left of the screen,
press the < > button to specify which side is up. Each press of the
< > button edits the movie rotation information as follows: [ ] →
[ ] → [ ].
Caution
Movies are played horizontally on the camera and via HDMI video output,
regardless of the [ :
Add rotate info ] setting ( ).
Movie orientation information of movies recorded with other cameras cannot be
edited with this camera.
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