My team has flown the same campus multiple times in an effort to create the most accurate point cloud possible but we are struggling to merge the projects effectively.
Flight 1: 2 60m pre-planned grid flights at 70% route overlap.
Point cloud result: The point clouds came together well but we realized that we needed more coverage of the buildings on site.
Flight 2: 5 40m pre-planned grid flights at 70% route overlap, Terrestrial photos of the buildings (The drone was carried by my partner) with significant photo overlap, 2 40m pre-planned circular flights at 10% angle around the main building, and several manual flights on the corners of the main building to connect terrestrial to grid flights.
Point cloud result: Attempting to create a single project with all of these flights at once resulted in a point cloud with the buildings floating beneath the landscape, which was skewed at an angle of around -15%. After breaking this project into several smaller projects, the terrestrial photos seemed to come out ok but the landscape was still very skewed. Deciding to use the acceptable data from the first flights (60m, 70%overlap) for the landscape, we attempted to merge the landscape point cloud with the terrestrial point cloud using MTPs. This again resulted in the buildings floating in a void beneath the landscape.
Attached is a photo demonstrating the skewed landscape and floating buildings.
Is there a better way to connect grid flights with terrestrially taken photos?