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Problems using point cloud LAS data in ArcGIS

 When I download LAS data from my missions and use in ArcGIS they do not work as expected.  I can display them but when I attempt to create a DTM or DSM from the point cloud data I get an error saying a table was not found. [VAT_projectname_LasD1]

 

Anyone know why this is occuring?  I don't have problems with standard Lidar data.

David Jones

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Keep in mind that our LAS files are georeferenced and that the X and Y dimensions are in degrees latitude and longitude while the Z dimension is in meters. This file type works with most of the big CAD and GIS programs. There is probably a conversion in LAStools that you can run the models through to get them into meters x meters x meters if that is what you are looking for. Also, our OBJ 3D model is in meters x meters x meters if you need a file that is already in that format. 

Try projecting from EPSG:4326 to EPSG:26916

Zane 0 votes
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Thanks Zane.  

The more I look at it something is not adding up.  When I create a LAS dataset and load the .las file in and calculate statistics the returns are all showing up as 100%.  I can load this dataset into ArcMap and it will display the data when "ALL" filters are turned on but not when "Ground" filter is turned on.  

David Jones 0 votes
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Thanks.  Does that mean the LAS data I get from MME is only capable of creating DSMs and not capable of creating DTMs?  Is there a way it can be classified in ArcGIS?  I don't think this is a limitation of the Mavic Pro's camera because Pix4D can create DTM's from it's imagery.  I'm basically a beginner at dealing with point cloud data.  I've had success using lidar datasets to create DTM's.  This is my first attempt at using drone data to accomplish this.

David Jones 0 votes
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There are a bunch of tools and plugins available for classifying point cloud data. This doesn't have anything to do with the camera you are using. 

Maps Made Easy provides a DEM (DSM) by default with all jobs. All at DTM is with respect to photogrammetric reproductions is a feature filtered DSM. There are tools available to do that as well. 

Point clouds are a hard place to start but keep in mind that this is not LiDAR data. The points are a surface measurement and there is no canopy penetration to the ground so trying to get a DTM out of it will require some advanced processing techniques. 

Zane 0 votes