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DOUBLE LAS ARE COMING

Hi we are facing some issues after processing drone images,
there are sudden jump in elevation DIFFERENCE after processing and creating DSM out of .las
and at some location double las appears at random locations.
can anyone plz let me know where we are going wrong so that we correct ourselves???

i have attached some images for reference to look in. Do check.

Hi, were all images acquired during the same flight? or do you have multiple flights that were combined?

I’ve seen this type of “double layer” in the point cloud before e.g. if two flights were made at different times of the day, this can result in different shadows on the area and in the software not recognizing that these images were taken at the same place. Thereafter, it creates two layers. This can be fixed by adding Manual Tie Points (MTPs) on the areas with two layers, making sure you mark these MTPs in images that were used to create both layers. Then, I would “Rematch and Optimize” (usually with projects with <500 images), otherwise you can rerun the project with the MTPs.

In any case, I would always recommend checking the quality of the sparse and dense point cloud in the rayCloud before running DSM/Ortho. First checking visually if there are multiple layers, then by clicking points and checking the reprojection error.

Hope this helps! If it does not correspond to your project, could you share your quality report?