Point cloud tiles misalignment

Dear all,

I have a problem with dense point clouds tiles. Pix4D generates high density point clouds with tiles. However, these tiles alignments are not well, in my project 50 cm! misalignments occured… Do anybody checked the tile alignments in density point cloud??
Please help me about it.

Ps: Densification settings were in default settings, I have used GCPs. And I have created single project, not any merged project.

Screencapture in the link.

Bests

https://drive.google.com/open?id=0B9CZcJOo5aFoTURuZnRuaXQyZHM&authuser=0

Hi!

I think the solution is to add manual tie points and reoptimize. When i have misalignment, manual tie points always make the trick.
wish you luck,
Marc

Hi Marc,
Thanks for your suggestion. I am working on it.
Before create dense point cloud, some manual tie points will make processing easy in large and images from different altitudes in same project.
Bests.
Mustafa

Dear all,

The common causes of misalignment can be:

  • problem with the georeference (GCPs or images coordinates)
  • the area to be mapped is very uniform (for example roads)
  • the images are of low quality (blurry)
  • different flight altitudes (different GSD)

To solve the problem you need to add Manual Tie Points (MTPs) and Reoptimize: https://support.pix4d.com/hc/en-us/articles/202560349-How-to-Add-Import-and-Mark-Manual-Tie-Points-with-the-rayCloud

Best regards,