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I have a Canadian lidar LAZ file, and it is in long/lat based in UTM10, sourced from LidarBC (https://governmentofbc.maps.arcgis.com/apps/MapSeries/index.html?appid=d06b37979b0c4709b7fcf2a1ed458e03).

I need to pass this into another app, but this second app expects data in a coordinate system with an EPSG code. To me, as the end user, the EPSG code is not critical, I just need a relevant code.

How can I convert the data file? Apologies if this is a stupid question, I am not a lidar expert. Up to now, most lidar files have been expressed using an EPSG system.

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    Please post a link (DropBox, WeTransfer, etc) to your LAZ.
    – Pointdump
    Commented Sep 5, 2022 at 8:28
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    UTM is projected not lat/long and there are EPSG code for it : spatialreference.org/ref/?search=utm+10N&srtext=Search
    – J.R
    Commented Sep 5, 2022 at 8:50
  • Thanks @J.R, I tried using 26910 and 32610, but the second app still errored. I am a little bit out of my depth here. Commented Sep 5, 2022 at 10:02
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    Steve, Using lasinfo in lastools reads the header, which shows the coordinate system as NAD83(CSRS) / UTM zone 10N + CGVD2013 height. So that would be EPSG:6653.
    – Pointdump
    Commented Sep 5, 2022 at 12:46
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    @Pointdump - This worked! Could you enter it as an answer so I can credit it to you please? Now the second app barfed at the file size, but it at least accepts the EPSG and gives me sensible visualisation, which is a step closer to success. Sweet. Commented Sep 5, 2022 at 18:57

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Using lasinfo in lastools, projection information in the header of the LAZ file shows:

COMPD_CS["NAD83(CSRS) / UTM zone 10N + CGVD2013 height - CGG2013 (meters)",PROJCS["NAD83(CSRS) / UTM zone 10N",GEOGCS["NAD83(CSRS)",DATUM["NAD83_Canadian_Spatial_Reference_System",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],TOWGS84[0,0,0,0,0,0,0],AUTHORITY["EPSG","6140"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4617"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",-123],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",500000],PARAMETER["false_northing",0],UNIT["meter",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","3157"]],VERT_CS["CGVD2013 height - CGG2013 (meters)",VERT_DATUM["Canadian Geodetic Vertical Datum of 2013",2005,AUTHORITY["EPSG","1127"]],UNIT["meter",1,AUTHORITY["EPSG","9001"]],AXIS["Up",UP],AUTHORITY["EPSG","6647"]]]
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    Superb, many thanks. Am now using lasClip to trim the files, much obliged! Commented Sep 5, 2022 at 20:17

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