Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 126)

Caution
Precautions when set to [ ] (White priority)
The warm color cast of subjects may fade.
When multiple light sources are included in the scene, the warm color cast of the
picture may not be reduced.
When using flash, the color tone will be the same as with [
] (Ambience priority).
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