Nikon D6 Reference Manual page 414

D
Before Shooting
•
Use an AF-S or AF-P lens.
•
Choose a release mode other than E .
•
For best results, we recommend that you choose mode A or M so that
aperture does not change during shooting.
•
We recommend that you stop aperture down two or three stops from
the maximum.
•
We recommend that you take all shots at the same ISO sensitivity.
•
Take a test shot at current settings.
•
We recommend using a tripod and disabling lens vibration reduction
(VR).
•
To ensure that shooting is not interrupted, use a fully-charged battery
or an AC adapter and power connector (available separately).
•
To prevent light entering via the viewfinder interfering with
photographs or exposure when your eye is from the viewfinder and
[Off] is selected for [Silent photography], raise the viewfinder eyepiece
shutter lever to close the viewfinder eyepiece shutter.
362
Varying Focus over a Series of Photos (Focus Shift Shooting)