Large 3D shapes and shadows are creating stitching issues

WebODM
1

I am mapping an agricultural field at different time intervals for monitoring. The field has an overhead sprinkler irrigation system in it. I keep having the issue of the irrigation system not stitching together correctly. I have been collecting images during solar noon, trying to decrease the effect of shadows in the images. Attached is a sample picture of my latest run, where the system did not stitch together correctly. The part of the irrigation that is not stitched properly together varies from run to run.

PNG
PNG1719×1042 727 KB

I am using Pix4D and a Phantom 4 for image acquisition. I have increased the overlap for 2D mapping in the Pix4D app to no prevail. I have tried a 3D (Double Grid) map with Pix4D to try to improve image acquisition as well, which is what was used for the sample image attached.

I am also using WebODM through Docker on Windows 10 Pro. My browser is sometimes Google chrome and other times Firefox (I haven’t found any differences with WebODM between the two).

I have not added a link to the images or my task output, because the images from this run was 1241 and the task was completed, just with errors in the ortho. The ortho is what I am mainly after at this time. I can add these if needed.

Parameters:
node-odm-1:3000 (auto)

min-num-features: 24000
resize-to: 1024
orthophoto-resolution: 3
orthophoto-cutline: true
fast-orthophoto: true
matcher-neighbors: 12

Thank you for any help, assistance, recommendations, or guidance anyone can provide.

2

Aside from flying at a higher elevation, this is a difficult one to improve.l The sprinklers will get partially reconstructed, but since they are so thin, they will cause lots of warping around them. Try to set --texturing-nadir-weight to 32 and --texturing-data-term to area.

3

Thank you for the help. I will add those parameters in a run today.

Increasing flight elevation sounds sort of counter-intuitive though, since by flying at a higher elevation will make the sprinklers even thinner. It appears it is becoming confused with the shade it casts at times. I am going to try a polarized lense during my next flight to see if that helps with some of the shade as well.