D-Link DNR-4020-16P User Manual page 26

Section 3 - Configuration
Day/Night
Choose whether to automatically or manually configure
D/N Settings
the day/night settings. If you select Timing, you will need to
designate a day/night schedule in the fields that appear. If you
select Auto, you will need to set the transition time between
day and night modes, as well as the delay before the transition
occurs.
The configuration options on this page are only available for
cameras being accessed via private protocol.
D-Link DNR-4020-16P User Manual 21