BioSonics details
The Details dialog box lists the following information that is specific to BioSonics data.
File
On angle echograms only:
- File name
- Minor-axis element distance polarity
- Major-axis element distance polarity
- Minor-axis center separation (mm)
- Major-axis center separation (mm)
- Minor-axis polarity
- Major-axis polarity
- Minor-axis angle offset (degrees)
- Major-axis angle offset (degrees)
- Minor phase aperture (degrees)
- Major phase aperture (degrees)
- Frequency (kHz)
- Absorption coefficient (dB/m) - see note.
- Pulse length (ms)
- Sound speed (m/s) - see note.
- (User) Calibration correction (dB)
- Salinity (ppt)
- Temperature (degrees C)
On Sv and TS echograms:
- File name
- Receive sensitivity (dB)
- Source level (dB)
- Power Setting (dB) displayed if PowerSetting < -0.00001
- Frequency (kHz)
- Absorption coefficient (dB/m) - see note.
- Pulse length (ms)
- Sound speed (m/s) - see note.
- (User) Calibration correction (dB)
- Minor-axis beam width (degrees)
- Major-axis beam width (degrees)
- Salinity (ppt)
- Temperature (degrees C)
Note: Excerpt from DT4 Data File Format Specification (August, 2004) p8: "The absorption and sound velocity values in the header are unreliable and should not be used. In particular, a single absorption value for all data channels, which may include transducers of different frequencies, is not appropriate. Instead, the proper values should be either provided by the user, or calculated using standard formulas based on the environmental conditions. You can use the temperature and salinity values present in this tuple and the frequency values present in channel descriptor tuples."