Multi beam echo sounder (MBES) capabilities are only supported in Hydromagic version 2025 and newer.
An additional license is required to record and process MBES data.

Multi beam calibration in Hydromagic

This document explains how to calibrate and setup Hydromagic in order to record your first multi beam survey. After configuring the multi beam plugin you have to configure some additional settings like the draft and sensor offsets to get accurate results.

Setting vessel shape and offsets

In Hydromagic, vessel shapes supplied with the software are mostly for use with a single beam echo sounder (i.e. they are configured with a single beam echo sounder position and offset). However, single beam vessel files can simply be converted to multi beam vessel files by changing the type of transducer.

To use a multi beam vessel shape, either create a new vessel design, convert an existing vessel design or use the "HydroScout MB 10.xml" file. To select or edit a vessel file, select the "Preferences..." option from the "option" menu in the main menu bar. Next select the "Map" tab where you can either select a vessel design, create one or edit an existing one using the "Vessel Designer".

Select or alter the vessel design from the "Map" tab.

Converting a single beam vessel design file

In this example we are going to show how to convert the "vessel3.xml" file to a multi beam vessel design, which only involves changing the sensor type of the transducer. First, start the "Vessel Designer" by clicking the "Editor..." button. When the "Vessel Designer" has been launched, click the "Open Design" button to open the "vessel3.xml" file.

The loaded vessel design (vessel3.xml) shown in the "Vessel Designer".

In the "Devices and Offsets" pane, you will see a list of all offsets, devices and sensors. When this pane is not visible, you can access it by selecting the "Devices and Offsets" option from the "View" => "Toolbars and Docking Windows" menu as shown in the screenshot below:

When hidden, use the view menu to show the pane.

To switch between a single beam and multi beam transducer, locate the item with the type set as "Transducer (SBES)" and double click it, or select it and click the "Modify Offset" button.

All sensors and offsets are displayed on the "Devices and Offsets" pane.

All the properties for this offset will be displayed, including offset position, color, description and offset type. Switch the offset type from "Transducer (SBES)" to "Transducer (MBES)". When the transducer has been mounted tilted, you can also enter the tilt angle in the "Roll" field in the "Offset Angles" section. Please check the offsets from the center of the vessel as well. They can be altered in the "Offset Coordinate" section, or you can set this position using the mouse by dragging the "TXD" symbol to the correct position in the vessel design window.

Switch the offset type from "SBES" to "MBES".

After changing the transducer type, you optionally save the "Vessel Design" with a different file name, by selecting the "Save Design As..." option from the file menu. Now close the "Vessel Designer" and click the "Browse..." button in the "Map" preferences tab to selected the newly created or modified vessel design file before proceeding to the next step.

Setting the correct transducer draft

The transducer draft is the offset between the bottom of the transducer and the water level. You have to enter the draft in the software as an absolute (positive) value. It is important that a multi beam compatible vessel design has been selected as explained above. To enter the draft, select "Preferences..." from the "Options" menu and select the "Calibration" tab.

Use the calibration tab to set the correct transducer offset.

Please note that the setting should be labeled "Transducer offset (MBES)", if not, the incorrect vessel design has been loaded. Enter the offset in the field in the project's units and click "OK" to store the value.