Stretched plots on Function Test Report

  • Issue: The Function Test report has stretched plots and fonts.
  • Versions affected: 15.3.19 and lower
  • Sensor platforms affected: all
  • Severity: low

Auto-Pick not ignoring SRA polygons

  • Issue: The Targ Detect function will pick targets inside SRA polygon types.
  • Versions affected: 15.3.19 and lower
  • Sensor platforms affected: all
  • Severity: low

Tx-Rx pairs setting not retained

  • Issue: The Tx-Rx pairs setting in the Targ Detect function is not retained after saving the PROCESSING interface
  • Versions affected: 15.3.19 and lower
  • Sensor platforms affected: all
  • Severity: medium

Extra Merge function in Flow

  • Issue: When restoring the AQ interface, an extra Raw-to-Merged step gets added to the P Flow1.
  • Versions affected: 15.3.19 and lower
  • Sensor platforms affected: all
  • Severity: medium

Installer not updating CompilerServices.UnSafe.dll

  • Issue: When upgrading to v15.3.19 some machines may get a message saying BTField cannot find the CompilerServices.UnSafe.dll. The workaround is to:
    1. Uninstall the BTField application in Windows Start/Installed apps. Do NOT uninstall SQL Server. Also, do NOT delete the c:\BTG Workspace folder.
    2. Run the v15.3.19 msi installer again.
  • Versions affected: 15.3.19 only
  • Sensor platforms affected: all
  • Severity: low

Elevation Offset in Merged H5 V1 Exports

  • Affected Software: BTField (all versions writing merged H5 V1 format)
  • Affected Configurations: Any multi-receiver array sensor (e.g., NATA-2) using merged H5 V1 export
  • Impact: Small elevation offset in exported sensor positions; effect is negligible under low-roll survey conditions and increases with terrain-induced roll
  • Status: Fix pending

Description

When BTField exports merged H5 V1 data, the Elevation field is written at the position of the first receiver (Rx #0) rather than at the GPS antenna. This introduces a lever arm offset that includes a lateral (cross-track) component. Because the offset is attitude-dependent, it produces spurious sensor height variation that cannot be removed by a simple constant correction.

When BTField re-imports this data, the import assumes Elevation is at the GPS antenna location and applies the lever arm correction a second time. This results in a double lever arm correction on the elevation values.

UTM coordinates (Easting, Northing) are not affected — they are computed directly from GPS Lat/Lon without a lever arm offset.

Affected Datasets

This issue affects any dataset exported as merged H5 V1 from a multi-receiver array where the first receiver is not co-located with the GPS antenna.

Any dataset that has already been exported and re-imported through BTField contains incorrect elevation values that cannot be corrected in place. Users should re-import affected merged H5 V1 data using a future version of BTField that provides the correct import logic.

Additional Note

The merged H5 V1 export also writes a hardcoded Geoid Separation value (−33.9 m) that may not match the actual survey location. This does not affect sensor Elevation but will produce an incorrect Height Above Ellipsoid (HAE) value in the file.

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