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Altitude correction using GCPs

Background

I am trying to correct the altitude of my project using GCPs.

  • Photos were taken using a DJI Mavic Enterprise Dual
  • My project is in UTM zone 16N
  • The altitude setting for my project is on MSL

Issue

After initial processing the tie point’s altitudes are between [-10 , -50], so I go in and add 5 3D GCPs, using draftlogic to determine UTM position and altitude above MSL and I get the results below after reprocessing step 1.

The automatic tie points also look less aligned with each other than before I added GCPs and the log shows several errors “unable to calculate bias matrix” or something like that.

Any suggestions for how to correct these issues and set correct MSL altitudes for my project? ( I have already made sure the geoid set in my project coordinate systems match the geoid used by google earth)

Thanks

A post was merged into an existing topic: Elevation off by ~200’