Edited on 4th of September 2020
For datasets acquired with DJI Phantom 4 RTK (P4RTK) we recommend the following workflow:
- No action required. (RTK) Image geolocation, horizontal and vertical accuracy is automatically recognized when importing the images. No action required.
- (PPK) After PPK postprocessing in a third party software, accurate image geolocation can be imported using the Image geolocation file (.csv, .txt, .dat). If necessary, edit the Accuracy Vert/Horz column to define the actual accuracy values. No action required.
- No action required. The optimized camera parameters for P4RTK (FC6310R_8.8_5472x3648) are already included and automatically recognized in the internal camera database.
- No action required. The correct vertical coordinates system is automatically recognized and set to WGS 84 Ellipsoid.
There is no need to change the default processing templates, e.g. 3D Maps, and the following processing options can be kept:
Can I process with the accurate geolocation pipeline?
- Accurate geolocation and orientation pipeline can be used when both, image geolocation and orientation, are precise.
We recommend using it for large datasets (faster processing) and when the dataset contains homogeneous or complex visual content (forest and dense vegetation, flat terrain with agriculture fields, snow, sand, and water surfaces).
More in the FAQ on the accurate geolocation pipeline.
Is it possible to use another vertical datum besides EGM84, EGM96, EGM2008 or the ellipsoid of the selected horizontal system?
- There is no direct way of selecting or importing a different vertical datum.
A workaround is to either provide the offset between the desired datum and the ellipsoid of the selected horizontal coordinate system or select the option Arbitrary Coordinate System for the outputs and the GCPs and import GCPs with coordinates in the coordinate system you specified.
More in the When to use the Geoid Height Above the Ellipsoid Function? and How to define Pix4D outputs with respect to a Geoid model articles.
Do I need to enable the linear shutter optimization?
- More in the Phantom 4 Pro Rolling shutter effect community post.
What could cause a big offset when comparing the results with checkpoints?
The horizontal offset could be caused by the horizontal grid corrections and transformations.
In some cases, when flying fast, close to the ground or in high winds, enabling the linear shutter optimization could reduce the offset.
The vertical offset could be present due to wrongly selected vertical coordinates system or custom geoid models.
In case the optimized camera parameters are far from the initial values, e.g. focal length, we recommend using the All Prior processing option.
- DJI Phantom 4 RTK: next gen accurate drone surveys - Official Pix4D blog post.
- First look at the Phantom 4 RTK - User test by Michael Cutfield.