2 Replies Latest reply on May 28, 2013 6:28 AM by yppmark

    Combine/Merge Multiple Rasters/DEM into Single One

      I need to combine/merge/mosaic 18 DEMs into one and then use it to generate slope data.

      What are the proper steps?  I've tried 'Mosaic to New Raster' but it didn't work (gave me a single dark piece of junk!)

      I'm attaching a few DEMs here.

      P.S.  I generated the DEMs using contour/breaklines in ArcGIS.

        • Re: Combine/Merge Multiple Rasters/DEM into Single One
          Use 'Mosaic to New Raster'. Make sure Pixel Type is set to 32_BIT_FLOAT. If you get a 'dark piece of junk', don't worry, the data is correct, you just need to calculate statistics so ArcMap can stretch it for display.
          • Re: Combine/Merge Multiple Rasters/DEM into Single One
            You're best off creating a mosaic dataset. For advantages of this over other formats refer to the arcgis online help.

            In ArcCatalog create a new File Geodatabase.

            Right click on new File Geodatabase then scroll to 'New' then select 'Mosaic Dataset'.

            Give the Mosaic Dataset an appropriate name then press okay.

            Now right click on new mosaic dataset in ArcCatalog and select 'Add Rasters'.

            In the Add Rasters to Mosaic Dataset GUI in 'Input Data' select dataset then navaigate and select the rasters you want to create the Mosaic Dataset with.

            In the advanced options section of the GUI tick 'Build Raster Pyramids', 'Calculate Statistics and 'Build Thumbnails'.

            Click okay to add the rasters to the mosaic dataset.
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