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I have a DEM raster (cell size 2.5*2.5). The spatial reference is lambert_Conformal_Conic_2SP and linear unit is Foot_US (0.304801).

Values for DEM was from 879.6 to 1426.78. I wanted to reproject it in UTM (cell size 10*10) and have linear unit in meters.

I simply used the project raster function and got an output raster that ranged from 879.63 to 1426.03. Does that seem right?

1 Answer 1

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When you project a raster from a coordinate system with a linear unit in feet to one with a linear unit in meters, it only changes the x and y units, not z. If you are working in ArcGIS and have the spatial analyst extension, you can use the "Times" tool to convert your elevation values from feet to meters. enter image description here

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  • Thanks for the response. Yes I am working in ArcGIS. So, first I need to use the times tool multiply my DEM in US_foot by 0.3048 and then do the reproject. Is that what you mean? Option 2 can be when I calculate slope from my previously re-pojected raster I can multiply the z value by 0.3048 ? Am I getting it right?
    – user65127
    Commented Nov 23, 2016 at 16:36
  • After you reproject your DEM, you would input that reprojected DEM (which still has elevation values in ft) into the "Input raster or constant value 1" field in the times tool. Then in the value 2 field, enter the conversion factor. Your output raster will now be entirely in meters.
    – Marina
    Commented Nov 23, 2016 at 16:46

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