Quality Check on GCPs - GCPs are used and the GCP error is more than 4 times the average GSD

I have run this project several times, carefully marking GCP points each time, but still getting red exclamation point for Georeferencing in the Quality Check/Quality Report. The GCPs were located with RTK GNSS system. I cannot find reason or error in workflow that would cause a GCP error is more than 4 times the average GSD.

Quality Report is attached. Thanks for any quidance

AccuracyAssessment2022-06-15_report.pdf (1.3 MB)

Since the texture of your project is very homogeneous (grass field), I would try changing the calibration method from standard to alternative. Also, what was your flight altitude and overlap?

Hi Jon,

From the quality report, we can see there is a difference between the initial position and the computed position.

If you believe your dataset has good image geolocation, please select Accurate Geolocation and Orientation in Step 1. Initial Processing > Calibration > Calibration Method > Accurate Geolocation and Orientation. Try also reducing the image scale to 1/2 or 1/4. You can take a look at this article. Menu Process > Processing Options… > 1. Initial Processing > Calibration

I hope this is helpful.


Thank you Andrew - I will give that a try. We flew 2 missions: one at 40 meters and the other at 50 meters. Working with the 40 meter AGL images first where I encountered the error.