Nikon D780 Reference Manual page 446

Option
[N-Log/HDR
output
options]
[View assist]
400 Connecting to Computers and TVs
Preserve details in highlights and shadows and avoid
over-saturated colors when recording movies. [N-Log]
is intended for footage that will be color graded during
post-production. [HDR (HLG)] is used to record
footage in HLG format for such applications as HDR
broadcasting.
•
The footage will be recorded directly to the external
device. It cannot be saved to the camera memory
card.
•
This option is available only when [10 bit] is selected
for [Output data depth] in modes other than EFCT.
•
The [ISO sensitivity settings] > [Maximum
sensitivity] and [ISO sensitivity (Mode M)] items in
the movie shooting menu can be set respectively to
values of from ISO 1600 to 25600 and from ISO 800 to
51200.
Choose [On] for a live preview of video footage
recorded with [N-Log] or [HDR (HLG)] selected for
[N-Log/HDR output options]. The colors in the
preview are simplified for enhanced contrast, but this
has no effect on the footage actually recorded.
Description