When the raw data files are viewed in the map they all show 0.00m as the depth whereas the data view shows a valid depth.

When the depth in the data view is correct and is displayed in green, the data should be recorded correctly. The map display will display a depth of 0.00 when:

1. The sounder is only sending low frequency depth readings to the Hydromagic software, while high frequency depths are displayed on the map.
2. The sounder is a single frequency model, or is sending only the high frequency depth readings to the software while low frequency depths are displayed on the map.

To toggle between high and low frequency depths values in the map display, select the "Preferences..." option from the "Options" menu. Next locate and click the "Map" tab and toggle the "Show low frequency depths" check box.

Starting from version 9.2, a warning message will be displayed when low frequency depths are currently displayed.