ArcGIS Pro and vertical transformations

[Pål_Herman_Sund]

Hi. Vertical transformations in ArcGIS is a bit confusing to me. 

Case 1: Local datum feet to meter transformation
I have received some data with a defined local vertical datum and made a definition for it (called HWI_local_feet). Made a similar one but defined it with meters (HWI_local_meters). I thought I could then define a transformation between the two with a "unit change" to scale from feet to meters via the Create Custom Geographic Transformation. Seems like the success is limited to put it that way 🙂 How can i get the feet to meters scaling for 3D features and LAS pointclouds?

Case 2: National (quasi) geoid model

For Norway there is a defined quasi geoid model for the NN2000 vertical datum (model is called HREF2018). Can the model be included in ArcGIS Pro somehow like other geoid models are part of the ArcGIS\CoordinateSystemsData\pedata\vertical\geoid installation  like other corresponding models are implemented?

thnx

Pål Herman

[Pål_Herman_Sund · Accepted solution]

If anyone sees this post, the answer is to install the ArcGIS Coordinate Systems Data component , downloadable from My Esri.  See help "https://pro.arcgis.com/en/pro-app/3.1/help/mapping/properties/arcgis-coordinate-systems-data.htm

[tikola]

Just like you said. I did just this same thing in Finland using our N2000 geoid model and basic approach is

1) Install Coordinate Systems Data just described above in your computer

2) Define your input data projection including the vertical projection

3) When running Project geoprocessing tool remind to tic Vertical radio button on and then it makes the vertical reprojection too. Of course requirement is that geoid models and transformations are found in installed package. In my case with Finnish elevation systems it was already there and all worked just as expected.

This approach works when data is in ArcGIS Pro formats - so that you can run it for example a las dataset that is converted to point feature class. I am not sure can you convert for example LAS to another LAS with different elevation system?

My case was drone based LAS where point cloud height were ellipsoidal and floated 20m above the ground. With this conversion that point feature class went to the correct orthometric height. So yes - ArcGIS Pro does elevation system conversions using the normal Project geoprocessing tool, but it requires bit more information and setup before it actually happens.