NorthStar 972 Quickstart Manual And Reference Manual page 36

Reference section 1 — Using the Chart Screen
32
Rotating the chart
ahead on the horizon may be different from
what's displayed on the screen.
Heading-up – This rotation is available
•
only if you have a heading sensor
installed and enabled. The chart rotates
as you travel to keep your heading
straight up on the screen. When you
select heading-up, the heading line on
the radar image points straight
upwards. The heading line allows you
to compare the radar image or the chart
with the view in front of the vessel.
Leg-up – The direction of the current
•
leg to a waypoint points straight
upwards on the screen. The 972 rotates
the chart whenever you start
navigating on a new leg, even if you
haven't turned the vessel yet.
Using chart rotation in browse mode
Chart rotation is most useful in vessel
mode. In browse mode, rotation is stabi-
lized to keep the chart and cursor from
jumping while you're browsing around on
the chart.
Course-up or Heading-up: Suppose
•
you're displaying the charts as
course-up or heading-up and you press
the cursor pad to use browse mode.
While in browse mode, the chart
rotation freezes. If your vessel changes
course, you won't see the chart rotate
to the new direction until you return to
vessel mode by pressing the Vessel key.
Only in vessel mode will the chart
rotate to follow your course angle.
Leg-up: If you're displaying charts in
•
browse mode as leg-up and the 972
switches to a new leg, the chart will
immediately rotate to the direction of
that new leg.
NOTES:
The edges of other charts in the 972's
built-in world chart folio are shown, in
addition to those installed. These edges are
shown as black or red dashed lines.
The lat/lon grid is labelled only when the
chart is north-up.
How rotating affects the chart and
radar
The rotation of the chart and the rotation
of the radar image interact under certain
circumstances, as described below. Assume
that the chart and radar are both north-up
at the start:
Northstar 972