Nikon D810 - Manual (Page 144)

120
g
: Aperture-Priority Auto
In aperture-priority auto, you choose the aperture while the
camera automatically selects the shutter speed that will produce
the optimal exposure.
To choose an aperture between the
minimum and maximum values for the
lens, rotate the sub-command dial
while the exposure meters are on.
Aperture can be locked at the selected
setting (0 126).
A
Non-CPU Lenses ( 0 419, 424)
Use the lens aperture ring to adjust
aperture. If the maximum aperture of the
lens has been specified using the Non-
CPU lens data item in setup menu (0 230)
when a non-CPU lens is attached, the
current f-number will be displayed in the
viewfinder and control panel, rounded to
the nearest full stop. Otherwise the
aperture displays will show only the number of stops (F, with
maximum aperture displayed as FA) and the f-number must be read
from the lens aperture ring.
Sub-command dial