Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 127)

[ ] Color Temperature
1.
Press the < > button ( ).
2.
Select < >.
Watch the top LCD panel as you turn the < > dial to select < >.
3.
Set the value.
Turn the < > dial to set the value.
The color temperature can be set from approx. 2500K to 10000K in
100K increments.
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