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I am using ArcGIS 10.3

I have 2 raster datasets with different coordinate systems, but they are the same county (just different databases). When I add them to the same map layer they are far away from each other. I want to be able to match up the two datasets so I can analyze them together.

I have tried Project Raster to change the coordinate system of one of the datasets but after 2 hours of trying to execute the function I gave up (it still said it was executing, no errors popped up while I was waiting).

Is that the correct function, should I just keep waiting, or can I use georeferencing to match my counties up even if they are in different systems?

*Another issue I am encounter is that the two images have different cell sizes (98X98 vs. 1X1). Is there a way to change cell size of one of the images?

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    Is it possible that one of the rasters has an incorrect coordinate system?
    – Paul
    Apr 2 '16 at 20:20
  • Yes you can use georeferencing. But tell us what your settings were for the project raster tool, and maybe we can resolve that.
    – Tom
    Apr 2 '16 at 22:02
  • I am inputting a raster that is NAD_1983_UTM_Zone15N (in Meters) and want to project it to NAD_1983_StatePlane_Texas_South_Central_FIPS_4204_Feet (in feet).
    – PiRho
    Apr 3 '16 at 0:23
  • A county-wide raster is going to take a long time to process. Depending on your computer's specs and the size of the raster, it could take 12 or more hours even. Unfortunately, you could project to it to find out waiting 12 hours was a complete waste of time. I generally run processes like that overnight so they're ready for me in the morning. Also, be leary of georeferencing a county-wide aerial.
    – Adam Kara
    Apr 4 '16 at 11:11
  • You should add the projection information specified in your comment to your question and specify which raster has which projection and units. It would be easier to craft an answer that is helpful if we have all the details.
    – jbchurchill
    Apr 4 '16 at 13:01
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You can do all of this with the "Project Raster" tool (in "Data Management Tools" > "Projections and Transformations" > "Raster"). There are a few things to consider here. If one of the rasters has a larger cell size, and it looks like one has a cell size of 98 (I'm not sure which one yet), you would do well to resample one of the rasters to the extent of the other (the one with the larger cells) if the goal is to analyze the rasters together. Lets assume raster a has the larger (98 m or feet) cells and raster b is the one we are going to reproject. I would approach this as follows. @Adam Kara is correct that it may take awhile. I also prefer to run these types of things when I'm going home for the day or even on a Friday to be sure I give the process enough time. Projection usually isn't that bad though.

  1. Open the Project Raster Tool and set the Input Raster to raster b and set the output using a name and location of your choosing.
  2. Set the Output Coordinate System by referencing raster a (just browse to it and select it). No geographic transformation is necessary since both rasters are in NAD 1983.
  3. Resampling Technique will depend on the data being projected. If it is numeric values (like elevation values) I would use Bilinear (best but slower) or Cubic (also ok). If the values are categorical (e.g. numbers representing land cover values), use the default (nearest). A little research into these options will explain why this is so.
  4. Output Cell Size - Use raster a as a reference again.

TIP: to ensure that the cells of both raster match perfectly click the "Environments" button and under "Processing Extent", set the "Snap Raster" to raster a.

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