I am trying to overlay a topographic map that is a raster and a road shapefile. The road shapefile was originally not defined. I defined the projection to NAD_1983_2011_Contiguous_USA_Albers and I did the same with the raster through its properties window.

I then used the project and made the input the road shapefile and the output coordinate system the raster. This created a new projection file. My assignment says all I have to do is upload the redefined files to ArcMap and they should overlay. They still won't. I checked both properties and the coordinate systems are the same. I don't know how to fix this.

  • Defining overwrites or sets the projection of the data. Project converts the data to a different projection. If the raster was already defined correctly and you redefined it to something incorrect, then no, it won't line up because it's using a different set of variables to convert. If your raster had a projection (was already georeferenced), you should leave it alone and only Define the shapefile which does not have one (assuming you know what it should be). If the raster doesn't have projection/georeference information, that's a whole other issue that neither Project nor Define will solve. – Chris W Oct 1 '15 at 0:51
  • neither of them were defined – Cori Sparks Oct 1 '15 at 1:16
  • I figured it out though. I was just using the wrong coordinate system for the spatial reference. – Cori Sparks Oct 1 '15 at 1:17

I figured it out for anyone who has a similar question: I needed to use a UTM coordinate system instead of the one I originally chose. The Raster file needed to be UTM 17 while the Shape file needed be UTM 16. If they were both the same it still wouldn't overlay.

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