This page describes the settings, necessary to an Echoview calculation, on the Calibration page of the Variable Properties dialog box for acoustic variables derived from SP70 data files.
We recommend you assess the suitability of the settings available on the Calibration pages for each acoustic variable. Quantitative calculation/analysis requires calibrated data which is achieved using correct calibration setting values (rather than default values). An ECS file enables you to modify calibration settings for variables in a fileset.
Note: The (red) default values on the Calibration pages are for illustration purposes only and have not been read from your data file. Read About calibration settings for further information.
A transducer can be selected in order to apply transducer geometry to the echogram. However, note that the 3dB beam angle setting is not used. Schools variables are not corrected for beam width. There is no correction for beam shape in 3D schools detection.
The SoundSpeed is used to calculate the datapoint range.
Echoview uses the the signal magnitudes stored in the data files and the Mulitbeam magnitudes to Sv algorithm to derive the Sv pings variable. This variable can utilize calibration settings for each beam (MultibeamBeamOffests) or apply a value that will be applied to all beams (CalibrationOffset). These settings can be set with an ECS file which must be added to a fileset.
Notes:
A transducer can be selected in order to apply transducer geometry to the echogram. However, note that the 3dB beam angle setting is not used. Schools variables are not corrected for beam width. There is no correction for beam shape in 3D schools detection.
The SoundSpeed is used to calculate the datapoint range.
About calibration settings
Entering calibration settings
Simrad data files
Raw variables derived from Simrad SP70 data