Diffraction Compensation - Nikon D780 Reference Manual

Diffraction Compensation

Select [On] to reduce diffraction at small apertures (high f/-
numbers).
•
To apply diffraction compensation to pictures taken with non-
CPU lenses, enter the lens data using the [Non-CPU lens data]
item in the setup menu.
G button U C photo shooting menu
Menu Guide > C The Photo Shooting Menu
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