Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 155)

Clarity
You can adjust image clarity, as determined by the contrast of image edges.
Set toward the negative end to make images look softer or toward the positive end for a
sharper appearance.
1.
Select [ : Clarity].
2.
Set the effect level.
Caution
Setting clarity may darken or lighten the areas around boundaries in high-contrast
images.
The effect of this setting is not shown in Live View images.
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