Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 72)

Basic Operations
Adjusting the Viewfinder
Holding the Camera
Shutter Button
< > Main Dial
< > Quick Control Dial
< > Multi-Controller
< >: Multi-Function Button
< >: AF Start Button/Smart Controller
< >: Multi-Function Lock
< > LCD Panel Illumination
Vertical Shooting
Time Display
Button Backlighting
< > Button
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