ok so this has been driving me crazy for two weeks. running a mapping mission over an agricultural field, pretty standard stuff, M300 with the P1 camera, flying at 120m, 80/70 overlap front and side. processing in Pix4Dmapper and everything looks great except for this one corner of the map where theres like a smearing effect and some of the rows in the field look doubled or offset. the rest of the orthomosaic is clean.

first thought was maybe some motion blur in that area but ive checked the images from that part of the flight and they look fine to me, sharp, good exposure. its not a GCP issue because i dont have any GCPs in that corner and i wonder if thats related but the rest of the map without GCPs nearby looks okay so idk.

quality report shows the reconstruction in that zone is marked as low confidence but doesnt really tell me why. anyone seen this before or know what parameters to look at

low confidence in a corner is almost always a flight coverage issue rather than a processing one, in my experience. corners are where the overlap starts to drop off because of how the mission planning calculates the grid - you might think you have 80/70 but the actual effective overlap at the very edge of the pattern can be significantly lower depending on your planning software and how it handles the turnaround legs. does the artifact area line up with where the aircraft was banking into its turns?

also what does the 2D keypoints map in the quality report look like for that area, is there a noticable drop in matched keypoints in that corner? that would confirm its a coverage thing. if so the fix is just adding some additional passes along that edge on the next flight, or extending your mission boundary by like 10-15% on all sides which i should probably just do automatically at this point honestly.

had almost exactly this happen to me and it turned out the wind was stronger than expected and the aircraft was drifting enough on some of the passes that the actual overlap wasnt matching what was planned. check if the artifact location corresponds to a particular heading - like was the wind pushing it on the east-west legs but not north-south or whatever. you can sometimes see it in the flight logs if you look at the actual position vs planned position. kind of annoying to diagnose but once you see it it makes sense