Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 254)

Movie Recording
Program AE
Shutter-Priority AE
Aperture-Priority AE
ISO Speed in < >, < >, and < > Modes
Manual Exposure Recording
ISO Speed in < > Mode
Shutter Speed
Still Photo Shooting
Information Display (Movie Recording)
Program AE
In < > recording mode, exposure is controlled automatically to suit the brightness.
1.
Set the Live View shooting/Movie shooting switch to < >.
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