Image Overlay; Add - Nikon Z 6II Reference Manual

Image Overlay

Image overlay combines existing photographs to create a single
picture that is saved separately from the originals. One NEF
(RAW) image can be overlaid on another using additive
blending ([Add]), or multiple images can be combined using
[Lighten] or [Darken].

Add

Overlay two NEF (RAW) images to create a single new JPEG
copy.
1
Select [Image overlay] in the
retouch menu.
Highlight [Image overlay] and press
2 .
G button U N retouch menu
N The Retouch Menu: Creating Retouched Copies
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