{"id":4991,"date":"2026-01-20T08:03:23","date_gmt":"2026-01-20T08:03:23","guid":{"rendered":"https:\/\/help.cadomation.com\/spcad\/docs\/spcadhelp\/dem-tools\/reproject-dem\/"},"modified":"2026-03-12T07:52:38","modified_gmt":"2026-03-12T07:52:38","slug":"demrep_sp","status":"publish","type":"docs","link":"https:\/\/help.cadomation.com\/spcad\/docs\/spcadhelp\/dem-tools\/demrep_sp\/","title":{"rendered":"Reproject DEM"},"content":{"rendered":"\n

Overview<\/h2>\n\n\n\n

The Reproject DEM<\/strong> Tool <\/strong>converts a DEM GeoTIFF from a geographic coordinate system<\/strong> (for example, WGS84 Lat\/Long<\/strong>) into the projected coordinate system assigned to your drawing<\/strong>. This makes the DEM align correctly with your CAD geometry, measurements, and other geospatial layers. <\/p>\n\n\n\n

If no coordinate system is assigned to the drawing, SPCAD shows \u201cCoordinate System NOT Assigned,\u201d<\/strong> and the tool will not proceed until you assign one. <\/p>\n\n\n\n

Access<\/strong> <\/h2>\n\n\n\n

DEM Tools \u2192 Reproject DEM<\/strong> <\/p>\n\n\n\n

When to use the<\/strong> Reproject DEM Tool<\/h2>\n\n\n\n

Use this tool when you have a DEM GeoTIFF that is: <\/p>\n\n\n\n

    \n
  • in Lat\/Long (degrees)<\/strong> or other non-projected systems, and <\/li>\n\n\n\n
  • You need it in a projected system (meters\/feet)<\/strong> to match your drawing and engineering workflows. <\/li>\n<\/ul>\n\n\n\n

    Typical examples: <\/p>\n\n\n\n

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    • DEM downloaded in WGS84 geographic coordinates <\/li>\n\n\n\n
    • DEM from web sources that doesn\u2019t match your project coordinate system <\/li>\n\n\n\n
    • DEM that inserts at an unexpected scale or location due to CRS mismatch <\/li>\n<\/ul>\n\n\n\n

      Prerequisite: Drawing Coordinate System<\/strong> <\/h2>\n\n\n\n

      Reproject DEM needs your drawing to have a coordinate system assigned. <\/p>\n\n\n\n

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      • If the drawing has no coordinate system<\/strong>, SPCAD displays the message: \n
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        • Coordinate System NOT Assigned<\/strong> <\/li>\n<\/ul>\n<\/li>\n\n\n\n
        • Assign a coordinate system using: \n
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          • Command: ACS_SP<\/strong> <\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n

            Workflow<\/strong> for using Reproject DEM Tool<\/h3>\n\n\n\n
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            1. (If needed) Assign the drawing coordinate system: \n
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              • Run ACS_SP<\/strong> and select the correct projected<\/strong> coordinate system for your project. <\/li>\n<\/ul>\n<\/li>\n\n\n\n
              • Run Reproject DEM<\/strong>. <\/li>\n\n\n\n
              • Browse and select the input GeoTIFF DEM<\/strong> file (the one in geographic \/ non-projected CRS). <\/li>\n\n\n\n
              • Choose the output file name and folder<\/strong>. <\/li>\n\n\n\n
              • SPCAD reprojects the DEM into the drawing\u2019s assigned coordinate system and writes the new GeoTIFF. <\/li>\n<\/ol>\n\n\n\n

                Tips<\/strong> <\/h4>\n\n\n\n
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                • Always set the coordinate system first:<\/strong> Reprojection is only as correct as the drawing CRS you choose. Make sure your project CRS is correct before creating outputs. <\/li>\n\n\n\n
                • Use projected CRS for design work:<\/strong> Grading, contours, volumes, and distances are more reliable in projected units (meters\/feet) than in degrees. <\/li>\n\n\n\n
                • Keep outputs organized:<\/strong> Save reprojected DEMs into a dedicated project folder (e.g., …\\Survey\\DEM\\Reprojected\\) so paths stay stable. <\/li>\n\n\n\n
                • Check alignment after reprojection:<\/strong> After inserting\/using the reprojected DEM, verify it matches known control points or site boundaries. <\/li>\n<\/ul>\n\n\n\n
                  Output<\/strong> <\/h5>\n\n\n\n
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                  • A new reprojected GeoTIFF DEM<\/strong> is saved at the output location you specify, using the same projected coordinate system as the drawing<\/strong>. <\/li>\n<\/ul>\n\n\n\n
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