I have a DEM that has a terrible baseline value, but otherwise is consistent with that value. Thus I need to raise the values of all pixels by exactly 65. How would one go about doing so in ArcMap and its toolbox functions.
Take a look at using the Raster Calculator. Ex:
Try out the Raster Calculator geoprocessing tool (requires Spatial Analyst extension).
Raster Calculator—Help | ArcGIS for Desktop
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