Using ChartsGPSMAP 400/500 Series Owner’s Manual 13• Off—turns the heading line off.• distance—sets the distance to the end of the heading line.• Time—sets the amount of time until you reach the end of the heading line.world Map—displays a basic world map or satellite imagery (when fullworld Map is selected).Spot depths—turns spot soundings on or off, and sets a dangerous depth.Safety Shading (only available when you are using a BlueChart g2 orBlueChart g2 Vision card)—identifies a selected depth. Areas on the chart withdepths shallower than the specified value are shaded in blue, while areas withdepths greater than the specified value are shaded in white. The contour isalways drawn at, or deeper than, the selected depth.Select auto to use the depth from the g2 Vision chart.Symbols—changes symbol preferences.• Navaid Size—adjusts the size of the navaid symbols shown on the map.• Navaid Type—selects the navaid symbol set (NOAA or IALA).• Land POis—turns the display of land POIs (points of interest) on or off• Light Sectors—turns the sector in which a navigational light is visible onor off. Selecting auto filters out light sectors, depending on the zoom level.• Chart borders—turns chart borders on when using a BlueChart g2 VisionSD card and you want to see what area the maps cover.• Photo Points—turns camera icons (page 19) on or off when using aBlueChart g2 Vision SD card.• Vehicle icon—allows you to select a boat or triangle that is large, medium,or small as your boat icon on the chart.Using the Split navigation ChartUse the Split Navigation chart to view two different zoom levels of theNavigation chart at the same time. The top half of the screen is zoomed in 10times closer than the bottom half of the screen. The Range (-/+) keys controlthe zoom level.Press MENU to view additional settings (page 9).Using Perspective 3DPerspective 3D provides a view from above and behind the boat (accordingto your course), and provides a visual navigation aid. This view is helpfulwhen navigating tricky shoals, reefs, bridges, or channels, and is beneficialwhen trying to identify entry routes and exit routes in unfamiliar harbors oranchorages.