Canon EOS-1D X Instruction Manual page 248

3 Menu Function Settings
Silent LV shooting
This function applies to still photo shooting. For details, see page
214.
Metering timer
You can change how long the exposure settings are displayed (AE
lock time).
[z5] Menu
Time code
You can set the time code. For details, see pages 245 and 246.
Silent Control
When [Enable h] is set, you can use the touch pad <h> and
Quick Control screen to change settings silently during movie
shooting. For details, see page 244.
Movie shooting button
When [V/o] is set, besides pressing the <B> button, you can
also press the shutter button completely or use Remote Switch RS-
80N3 (sold separately) or Timer Remote Controller TC-80N3 (sold
separately) to start/stop the movie shooting (p.185). However, when
[V/o] is set, still photo shooting is not possible (p.236).
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