New in Echoview 4.20
for users of data from Simrad echosounders

Note: Simrad is a subsidiary of Kongsberg. See also New for users of Kongsberg echosounders

This page summarizes the new features, improvements and other changes that have been implemented in Echoview 4.20 which specifically affect the use of data from Simrad echosounders.

Simrad Ex60 calibration changes

When using From first ping calibration Echoview will now read the Major axis 3dB angle and Minor axis 3dB beam angle from the data file. These transducer settings will be listed on the Calibration page of the Variable Properties dialog box and only those settings will be used for calculations. EV files from Echoview versions prior to 4.20, when opened, will be updated to adopt the current behavior.

When you choose to calibrate Manually, these transducer settings must be entered on the Transducer Properties dialog box - in other words this process is unchanged.

These changes also apply to variables derived from Simrad ME70 data.

Simrad SP70 details

The details dialog lists ping details read from the SP70 data file.

Simrad SH80 details

The details dialog lists ping details read from the SH800 data file.

Noise calculations for Ex60 and EK500 data

A bug with noise calculations has been fixed. Noise calculations involving Time varied thresholds (TVT), Sv_noise, ABC_noise or NASC_noise now use TVG range correction if it has been applied on the Calibration 2 page of the Variable Properties dialog box for Ex60 and Ex500 data (or on the Calibration page of virtual variables that use Ex60 or Ex500 data).

Previously, Echoview did not account for TVG range correction in such calculations. As a consequence there may be small but significant errors in the processed data. The errors are of the order of 0.5dB (at 2m) to 0.05 dB (at 17m).

For further information refer to Background noise in Echoview: Time-varied threshold and Background noise subtraction.

Error using Apply calibration setting

Echoview 4.10 (prior to Echoview 4.10.66) contained a bug where when adding Ex60 data files to a fileset the Apply calibration settings option From first ping was incorrectly applying default calibration settings to the variable. This has been corrected in Echoview 4.10.66 and 4.20.

For further information refer to Calibration settings for Ex60 raw data.

See also: New features in Echoview 4.20 for a description of changes that may affect you but are not specific to data from Simrad echosounders.