Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 137)

Naming Custom White Balances
You can add a name (caption) to the five registered custom white balances (custom white
balance nos. 1–5).
1.
Select the custom white balance number.
On the [ Set Custom WB ] screen, select the number of the registered
custom white balance to add a name to.
2.
Select [Edit WB name].
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