Spatial analysis tools such as the Raster Calculator and Minus tools can provide powerful insights on raster value differences between raster images that are geographically overlapping. In ArcGIS Desktop, these tools are located in the Spatial Analyst toolbox. Alternatively, environments without the ArcGIS Spatial Analyst extension can use the Difference function from the Image Analysis window.
Note: The Raster Calculator and Minus tools require a Spatial Analyst license.
The instructions provided describe the steps to find raster value differences between two rasters. Option A describes the workflow when using the Raster Calculator tool from the Map Algebra toolset, whereas Option B describes the workflow when using the Minus tool from the Math toolset. Option C describes the steps to find the raster value differences using the Difference tool from the Image Analysis window, which does not require an extension.
Note: Ensure the pixel size and projections of both rasters are the same. If necessary, use the Resample and Project Raster tools from the Data Management toolbox to change the pixel size and projection of the rasters respectively. To ensure the accuracy of the output raster, the extents of the rasters can be aligned using the Clip tool.