Step in point cloud

Hi, I’ve processed the data as I do normally, but when interrogating the point cloud there is a visible step in height of approximately 1M.
The only difference being is the data was captured on separate occasions, GCP’s were used at the point of capture on both occasions.
I’ve processed the captured data separately and then merged, I’ve also processed the data in one go, and on both occasions the same step between the two days of data acquisition is noticeable.
Other than returning to site and capturing the data in one flight and then reprocessing I’m unsure how to resolve the issue.
Any help would be gratefully appreciated.

Hi @richard.shepherd

Welcome to the Pix4D community :handshake: .

This step could be due to several factors, such as differences in lighting conditions or changes in the environment between the two flights. Here are a few suggestions to help resolve this issue:

  • Ensure that the GCPs used for both flights are accurately marked and have the correct coordinates.
  • Check if the GCPs have been marked on enough images. Each GCP should be marked in at least 2 images, but it is recommended to mark them on more project images.
  • Review the projection error for each GCP shown in the quality report. All projection error values should be less than 1 pixel. If the values reported are greater than 1 pixel, carefully remark the images.
  • Consider adding more MTPs to the project, especially in areas with complex topography and in the overlap area between the two sub-projects.