Holes in Point Cloud near Ground Control Points

PIX4Dmapper
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I have just begun to use Pix4d Mapper. I have a question regarding point cloud creation. I have two control points on a portion of my project, where the point cloud is absent. I do not know what to do from here and would appreciate any input people have.

I have looked up various forums and here are some clarifications:

  1. I do not think that picture overlap is a problem - although, my lighting in some areas changes slightly.

  2. I used 5+ images for my ground control points - only the ones towards the center. These are the only two GCPs that are acting strange. I omitted the ones on the edge.

  3. There seems to be a decrease in point cloud density near my other control points. See attachment 2.1 - this is the worst usable one. This is generally true amongst my other control points; however, it did not give me a void like GCP 6 and 7.

  4. Attachment 11 is the quality report uploaded as a PDF, hopefully this is OK on this forum.

Hopefully I gave enough to begin trouble shooting. Thank you for your help.

One of the things I learned from the forums is that you guys love snips so below are a bunch of snips:

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I find it bizarre that I pay for a monthly subscription and can only embed one media post - this will not be efficient.

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Attachment 2.1

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Attachment 10

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q report.pdf (1.2 MB)
Attachment 11 - Quality Report.

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It looks like you used 3 flight lines which is good. Overlap looks good.

Why did you choose Custom Image Scale and 1/2? Was this for trouble shooting.
The Phantom 4 RTK offers quality images and as long as the target is suited for photogrammetry which your project looks to be, use full image scale.

Also why are you using all prior? Did you run it and have camera optimization above 5%?

I would change the following:

Initial Processing
Use Full Image scale.
Use Aerial Grid or Corridor
Use Camera Optimization All

Point Cloud
On your point cloud settings, try the setting Minimum Number of matches at 3. this should densify your point cloud more. But it will most likely also introduce possibly lower quality points and noise.

14

The problem was that my drone operator lost connection to his base station for alot of the pictures. He is flying the DJI Phantom 4 RTK. We reflew the site without the base station and only using the local coordinate system using a hotspot, connecting the controller to the internet.

Thank you jaja6009 for your input. There was no pix4d solution for this one. We needed some better methodology.