Problem with a project. Surface wrapped in a sphere

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
1

I am working with the latest version of Pix4DMapper, and I write to you because I have found some difficulties solving a model.

I have downloaded the image dataset of “Paris-Le Bourget Airport” model example from the SenseFly web (https://www.sensefly.com/drones/example-datasets.html ), and I have run the step one (Initial processing in Pix4D) and the result that I have obtained is the one showed below.

As you can see, the camera calibration is not correct, the estimated camera positions and the points are wrapped in a sphere. The reconstructed surface is flat and I obtain a curved one. I have checked the report uploaded in SenseFly web and the parameters seem to be the same, but they don´t have this problem with the surface.

I would like to know the options that I should check to detect the origin of this failure. I think that the problem could be the coordinate system, but it seems to be the same that in the report.

Thank you.

2

Hello,

I don’t the know the camera that was used, but if it has a rolling shutter then I guess this is what Pix4D explains in this other post.

Cheers

3

No Answer? Ever find out?

 

4

I had the same issue when processing the example dataset from senseFly. There seems to be an issue with the timestamps on the images that seem to be mixed up (green lines in all directions): 

This could contribute to the issue and might indicate other issues with the image tags. I tried processing without taking the timestamps into account but it did not improve the result, so there is probably something else going on. 

I also tried processing with the Rolling Shutter correction, but it did not work for me. 

In such cases, I would add Ground Control Points (GCPs) to the project that should help constrain the project correctly.