Canon EOS 5D Mark III Instruction Manual page 246

3 Menu Function Settings
By pressing the <B> button, you can change the information
displayed on the screen.
You can append a time code to the HDMI output image (p.241).
[52] Menu
HDMI frame rate
You can set the HDMI output frame rate to [Auto], [24p], or [60i/50i].
When you record movie from the HDMI output to a commercially-
available external recording device, set the frame rate to match the
external recording device's frame rate.
If the frame rate set manually is not compatible with the external
recording device, the frame rate will be set automatically.
If [Movie recording size] is set to frame rate 4 when [HDMI frame
rate: 60i] is set, "2-3 pulldown" will be performed.
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