Troubles with Pix4Dmapper

Hello,

I have two doubts about the Pix4Dmapper. First one, when I import the images, the software estimates the camera model from EXIF. However, the parameters are shown different from the real parameters. Should I use the estimated parameters or should I change it? My drone is the DJI Phantom 4 Pro.

The second question is about the orthomosaic. The measurements obtained from the orthomosaic show a very high error, while in the point cloud the error is much lower. What is the reason for that? Mind that I’m using a very high resolution (GSD=1,1mm).

Best regards,

Rui Martins

 

http://docdro.id/ZA8Pbg3 

Hi Rui,

To process the images, I recommend to select the camera model that we optimized for the camera of DJI Phantom 4 Pro (FC6310) from the list. This camera model should have a database icon (learn more). If the parameters are imported from the EXIF, you should see a camera icon instead.

About the orthomosaic and the accuracy, the camera has a rolling shutter which can be an issue for the reconstruction depending on the flight conditions and the area that is mapped. To mitigate the effect, we suggest to apply a specific algorithm especially for flights with a regular pattern (lines). To learn more about this issue and apply the linear rolling shutter correction, click here.

If the results are not satisfying, you can try the following together with the linear rolling shutter algorithm:

  1. On the menu bar, click Process > Processing Options…
  2. Select 1. Initial Processing and then the tab Calibration.
  3. Make sure the Advanced box at the bottom left corner is checked.
  4. In the section Calibration, from the drop-down list for the Internal Parameters Optimization, select All Prior.
  5. Click OK.
  6. On the menu bar, click View > Processing.
  7. On the processing bar, check 1. Initial Processing and uncheck steps 2 and 3.
  8. Click Start to re-run step 1.

Hope it helps!

Hello,

Thanks for the recommendations but unfortunately the problem wasn’t solved. The error associated to the orthomosaic is still the same.

I have another question. Is it possible to measure the orthomosaic in Pix4dmapper? I have measured the orthomosaic in other software and it’s possible that the error is there. However, in the same software I import the point cloud and the measurements are good as in Pix4dmapper.

Best regards,

Rui Martins

Martins,

It is not possible to measure in the Mosaic Editor of Pix4Dmapper but you can do it on our cloud by uploading the GeoTIFF orthomosaic (learn more). To inspect the 2D results, I would recommend Quantum GIS (QGIS) that is free and open source: https://qgis.org/en/site/forusers/download.html. What have been using so far?