Convert elipsodal height to local NN2000 format height

I am using Mavic 3E with RTK processed on WEBODM/Lightning service. The point cloud is produced with ellipsoidal height. In Norway, they have a cartographic height standard called NN2000.

I would like to convert the point cloud height to NN2000. I have a raster (https://cdn.proj.org/no_kv_HREF2018B_NN2000_EUREF89.tif) that tells me the difference between ellipsoidal height and NN2000. Is there any way I can tell WEBODM to give me the point cloud height in NN2000 ? Or - is there anyway I can use this raster to convert the point cloud height in Qgis to NN2000 ?

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Hiya - using PDAL to modify the point cloud might work best, take a look at this tutorial:

https://pdal.io/en/stable/tutorial/grid-shift.html

It’s relatively straightforward to set up a pipeline to ingest and output LAZ/COPC/EPT and do the transformation on the way. Best to take a small chunk of the point cloud first to test on :wink:

Hope that helps!

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Hej from Sweden!

I only set 3011(Sweref99 18 00) in the GCP ESPG line and export the pointcloud as 3011.
Then the hights get right for me.

Might work for you if you got GCP’s.

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Thanks for the replay - I will try out both options :slight_smile:

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Another option is to open it in CloudCompare and reproject it there. You mark known points and then write the true coordinates below and transform. It works well.