How can one change a coordinate system for a .lasd (Lidar) dataset?
The file is currently in UTM_Zone_15N and I am trying to convert it to IL_East.
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It only takes a minute to sign up.Sign up to join this community
Depending on the ArcGIS version, some LiDAR tools will allow reprojecting through the Environment settings: Output Coordinate System.
For example, the Tile LAS tool:
The output LAS tiles can be reprojected by ... specifying an Output Coordinate System in the environment settings ... .
LiDAR (.las) files and LASdataset files (.lasd) cannot be reprojected within ArcGIS.
A .lasd file is a LAS dataset file developed by ESRI.
The LAS dataset does not import point data contained in the LAS files; it simply stores reference to these LAS files and surface constraints.
According to ArcGIS Help 10.1 one can set a spatial reference to a LAS dataset going to the ArcCatalog, LAS Dataset properties, and then,
XY Coordinate System tab.
However, this won't change/reproject the actual .las files. It is only recommended when the .las files do not originally contain the spatial reference and one knows which CRS they belong to.
Strongly recommend reading: LAS dataset considerations - Spatial reference, which includes ESRI's constraints about this topic.
Alternatively, there are other software which will allow reprojection of .las files (example).
You can use the las2las function in libLAS to reproject las files.
Here's some help regarding the lastolas suggestion from Tim in MN.
The issue is that the way that the projection information is written in the LAS files is not being properly parsed by ArcGIS and it is appearing in the southern hemisphere. I have validated that the projection information is correct but that ArcGIS reads it incorrectly.
The solution is to redo the header of the las files and update the projection information. I do this using LAS2LAS like so:
Las2las.exe –I -o -remove_all_vlrs -utm 15T
So I did one file and the command line was like so:
las2las.exe -i 4342-01-25_d_c.laz -o 4342-01-25_d_c.las -remove_all_vlrs -utm 15T
The –remove_all_vlrs switch removes all of the existing variable length records in the LAZ file, including the existing projection information that ArcGIS fails on. The –utm 15T adds a vlr that has the projection information in a format that ArcGIS understands.