Virtual surveyor can help you to align your photogrammetry outputs with your elevation datum


The proper elevation datum needs to be set in your photogrammetry process. That is the processing step before you start working in Virtual Surveyor. Nevertheless, most of the time your image processing software only exports Ellipsoidal height unless you use GCPs or adjust the 3D model to a global or local geoid model.


Virtual Surveyor provides a quick and easy way to adjust your data to local heights. 


Overview

  1. Import the survey dataset.
  2. Select the elevation terrain in the project view and go to the TOOLS tab.
  3. Set the offset Z value in the Offset group.
  4. Press Enter.
  5. The elevation terrain is moved up or down according the offset value.










Tips and Tricks

  • Objects (points, polylines, surfaces...) placed on the initial terrain will not follow the offset. The best practice is to first offset the terrain and then perform your survey.
  • You can remove the offset by entering a zero value as the Offset Z. The terrain will revert to its original state.
  • Refer to the site supervisor to determine the offset value between ellipsoidal height and local height. You can also use the geoid height value if you want to offset from ellipsoidal height to geoidal height. Refer to you national geographic institute to know more about the geoid height values.