Avidyne IFD540 Pilot's Manual page 108

The charts can be pinch-zoomed and panned or knob zoomed to
see close ups of the airfield diagram.
If you did not select or use a published approach via Charts, the
local airfield diagram can still be accessed. Select "CHART" tab
of the MAP page and then use the left-hand LSKs to select the
desired airfield diagram.
Lighting
Some pilots prefer to use the Charts pages in the daytime lighting
scheme at all times and some prefer the nighttime lighting
scheme. In order to provide that flexibility, a separate "Chart
Day/Night Mode" option (Auto, Day, Night) has been provided on
the User Options LSK of the Setup tab on the AUX page. "Day"
will always provide a bright white background for readability.
"Night" will always turn the bright white backlighting off. "Auto"
will use the additional "Chart Auto Mode" selection (Sensor,
DimBus) on the User Options LSK of the Setup tab on the AUX
page to control the definition of Auto.
Water Marking/Expired Data
Charts that have been expired for 60 or more days will still be
displayed and readable indefinitely but a watermark "Not for
Navigation" will be depicted on each chart. Expired charts will not
display the flight plan overlay.
Updating Charts
Procedures for updating Charts are described in Section 6 of this
manual.
3-32 Map Pages