Large Error on Linear Project

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
1

Hello:

 

I’ve been using Pix4D for a few years and am very familiar with the software.  We recently flew +/- 1200-LF of roadway at 60-M in elevation at 5-MPS w/ +/- 90% overlap.  Generally we get very good results with these specs.  However, for some reason the vertical error is significant.  See attached Quality Report.

 

Does anyone see anything in the report that may indicate why the error is so high?  Thank you for your help.

 

  • Jim

 

 

 

2

Hello James,

I cannot see the Quality Report, I suppose there was an error when uploading it.

Would you please send it again?

If you prefer, you can open a support ticket where it is easier to exchange files and projects.

Thank you very much.

3

I realized that but I can’t load a PDF?  Anyway - here are a series of jpg of the QR.  Thank you for reviewing.

4

Hello again,

Thanks for the feedback.

By looking at the Quality Report:

  • I would change the GCPs accuracy which is set to 0.02 ft. I would use at least 0.06 as you have done with the last GCP.

  • GCP 3015 has a high error. I would review the marks just in case there was a mistake. As it is a GCP, it is used in the adjustment and in case it is wrong it might be the cause of the large errors in the checkpoints.

  • I am not sure what was the speed of the drone but I would try to apply the rolling shutter correction too.

  • What is the accuracy of the geotags?

Please let me know how it goes.

Regards.