Navigation security

The information dialog of the chart (refer to previous paragraph) displays important information for navigation, such as:

á Depth units

á Type of projection ( most of the timeÊ: mercator )

á Chart Geodetic Datum (most of the time : NAD83)

Note that, according to BSB Electronic Charts, NAD83 and WGS84 are assumed to be the same for use with NOAA navigation charts.

á Latitude and longitude shifts from chart geodetic datum to WGS84 geodetic datum

In the bottom of the chart window, a small icon reminds you the geodetic datum of the currently displayed chart. It is either WGS84, local or unknown (only available in ãChart by chart modeä).

All those reference informations may change from chart to chart. Be careful to check those informations (and the consistancy with your equipments: GPS, depth echo-sounder ·) for a safe use of the charts.