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missing "grid" in point cloud, results in XYZ output covered in spikes

last month I used a Trimble ebee to fly over a large construction site (160ha) and the flight and processing worked well. this month I have used the exact same flight path, UAV, GCPs etc. conditions on site were similar to the previous month. I used the XYZ output on a 40cm grid as I did last month and triangulated and contoured in in my survey software. I noticed millions of spikes up to 2m high over the entire site. the contours are very noisey. The orthomosaic looks fine. I then went to the ray cloud in Pix4D and noticed that it looks like there are “rows” of missing data and it has not fully densified. any ideas?? I have used the same settings this month compared to last. I have attached screenshots of the point cloud in pix 4d. Also a link to the PDF report in which I have noticed that it does not display the quality of the ATP which the white/grey/black triangles.
Unfortunately due to the size of the data package it takes approx. 8hrs to re-process and I need usable data asap so I don’t want to just blindly hit re-process and cross my fingers other wise I feel that I will likely just waste my time.

 

a link to the PDF report; https://www.dropbox.com/s/stct6gch4bnsxcz/160629%20newport_report.pdf?dl=0 

Hello Lee, 

What happens in this case is that a part of your project is very far away from the visible Point Cloud. 

You could try to add a processing area in your project, in that way your project will be “restricted” in a way and avoid the stretching you can see in the rayCloud.

more info here: https://support.pix4d.com/hc/en-us/articles/202560179

Best Regards,