Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 877)

: Cycle Between the Set Functions
Each press of the < > button switches from one shooting function setting to the next.
* 9: To access the detailed settings screen when the setting screen is displayed, press the < >
button. You can set the the functions that the camera switches among. Turn the < > dial to
select an item, then press < > to add a checkmark [ ]. Select [ OK ] to register the setting.
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