Sound velocity sensor (SVS- eg MiniSVS - Valeport) records the sound velocity speed at the multibeam head and the data is recorded and used for the beam forming calculations in the mbes software. When the multibeam data is imported in NaviEdit, if the svs was interfaced as an instrument in the acquisition software(eg Auxiliary sensor - MiniSVS in NaviScan) it will be shown as an instrument in both Header Editor and Data Editor (separate and in the multibeam window), if not it can only be seen in the Data Editor under Multibeam window by clicking on the Open sound velocity edit view button as shown below:
Fig 1. Multibeam window - SVS graph
Only under the Multibeam window and Scan Sound velocity edit changes to the svs data can be done and saved back to correct the beam forming.
SVS records at the multibeam head can be exported as Sound velocity track ascii .sv format starting with the NaviEdit version 9.2.1 (see chapter 3).
Fig. 2 Export sound velocity speed at the mbes head
If the SVS values must be adjusted due to issues seen in the multibeam data (and this is not solved just by editing the existing values as explained above), this can be done using the feature called Adjust beam forming that is enabled with a right click on the Multibeam window. This is available starting with version 9 of NaviEdit for all types of formats (chapter 7.3.1) and with version 8.8 only for Kongsberg formats (see chapter 2.3).
Fig 3 Adjust beam forming
The options included in this feature are User value, Single beam channel and Auxiliary channel. When the Change SV at the heads to input value is ticked the input will be taken into account and beam forming adjusted once OK is pressed. The adjustment is done based on the sound velocity difference between the sound velocity registered at each scan and the sound velocity measured at the sound velocity probe.
Fig 4 Adjust beam forming options
If the above is meant to be applied on the files, make a copy of the original file for comparison with the results of altering the original SVS data.