Calibration settings for SM2000 and SM20 data

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 SM2000 and SM20 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.

Simrad Mesotech SM2000 FR and Kongsberg Mesotech SM20

P	Setting is used in calculating datapoint values.
	Setting is not used in calculating datapoint values but may be used for other purposes, see Additional uses of Calibration settings
	Setting is not available for this variable.

Calibration setting	Details
	SM2000 raw data and SM20 data					SM2000 beamformed data
	magnitude raw beam pings	phase raw beam pings	magnitude beamformed raw beam pings	phase beamformed raw beam pings	Sv beamformed raw beam pings	Sv beamformed pings	magnitude complex beamformed pings	phase complex beamformed pings	magintude beamformed pings
BeamOffsets					P	P
CalibrationOffset					P	P
Frequency (kHz)
SM2000BeamsToForm+			P	P	P
SM2000Sector+ (degrees)			P	P	P
SoundSpeed+ (m/s)			P	P	P
SM2000HeadType* (degrees)	P	P	P	P	P
SM2000Radius* (m)	P	P	P	P	P
SM2000Spacing* (degrees)	P	P	P	P	P

Notes:

A transducer can be selected in order to apply transducer geometry to the echogram.
+ SM2000BeamsToForm, SM2000Sector amd SoundSpeed are used by the beamforming algorithm.
* SM2000HeadType, SM2000Radius, SM2000Spacing can be used to specify the SM2000 Head used for logging. SM2000Spacing is also known as the the SM2000 Interelement spacing (degrees). Refer to Typical Head values or specify the values used with an ECS file. If the head properties were changed during logging, the data files with different settings must be entered in separate filesets.
Magnitude raw beam pings variables and phase raw beam pings variables in the same fileset share the same calibration settings.
Magnitude beamformed raw beam pings variables and phase beamformed raw beam pings variables in the same fileset share the same calibration settings.
Magnitude beamformed pings variables and phase beamformed pings variables in the same fileset share the same calibration settings.
A transducer can be selected in order to apply transducer geometry to the echogram. 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.

Typical Head values

Head type (degrees)	Head radius (meters)	Head spacing (degrees)
180	0.1100	1.9620
120	0.2000	1.1160
90	0.3874	1.2000
60	0.4293	0.8496

Calibration settings for SM2000 and SM20 data

Simrad Mesotech SM2000 FR and Kongsberg Mesotech SM20

Typical Head values

See also