Nikon D500 - Manual (Page 173)

173 Menu Guide
Copy photographs in Black-and-white,
Sepia, or Cyanotype (blue and white
monochrome).
Selecting Sepia or Cyanotype
displays a preview of the
selected image; press
1 to
increase color saturation, 3 to
decrease. Press J to create a
monochrome copy.
Monochrome
G button
➜ N retouch menu
Increase
saturation
Decrease
saturation