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I am working in ArcMap 10.2.2. I am trying to project a NED 3m dataset from a Geographic Coordinate System to a Projected Coordinate System. The output rasters pixels do not overlap the original rasters. I have used the snap to raster in Environments, both with the Background processing enabled and not. I have tried running the projection in ArcCatolog and Arcmap. Does anyone have any idea how to align these rasters.

  • What are the "original rasters?' – Chris Strother Jul 22 '15 at 14:42
  • The "original" is a 3 m elevation raster with the spatial reference GCS_North_America_1983 that is clipped down to the study area. – V0921psc Jul 22 '15 at 14:47
  • I guess that I'm confused. If you are projecting to a new coordinate system, shouldn't you expect some (even small) amount of shifting? Are you using the same datum? – Chris Strother Jul 22 '15 at 14:54
  • They are in different datums. So a shift should be expected, they should not line up? – V0921psc Jul 22 '15 at 15:00
  • That's correct, see my answer for complete explanation. – Chris Strother Jul 22 '15 at 15:08
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You will not be able to align these rasters in different coordinate systems especially since they are built from different datum. In the screen capture here, I have taken a raster with UTM projected coordinates and reprojected to GCS WGS 84. You can see the difference in linear shift of the corner of roughly 60m. Unless all of your rasters are projected in the same system, there's no way to guarantee registration between cells. enter image description here

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Are the raster pixel sizes the same? If one is 3m and the other is 10m then there is no way that they can correctly overlap. I would look into that first. Second, if there is a common raster that you can clip it to outside of the ones you are using that shares that same cell size, then I would use that. Double check on the cell sizes to make sure that there aren't any discrepancies. The coordinate system change may cause some shifting as well, depending on which systems you are using. I would try to change the coordinate system within ArcCatalog by right clicking the layer, and then going to properties, and changing the system from the geographic coordinate system to the projected coordinate system. Then reload the data into the map.

  • I am only using 1 raster, the raster I want to project, to a Projected Coordinate system. The product of the projection is the raster that is not overlapping with it's original, the one that is in the geographic coordinate system. The raster is already clipped to the area that I need it to be, I also ran the projection on the entire state, but had the same issues. I will attempt the ArcCatalog suggestion now. . – V0921psc Jul 22 '15 at 14:54
  • Let me know if it works and I'll edit the answer. – Cameron Sloan Jul 22 '15 at 14:56

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