Geoprocessing Raster of Different Projections

Discussion created by chcarlson on Aug 9, 2011
Latest reply on Aug 10, 2011 by chcarlson
I have been over this and over this with a co-worker many times.  Can you use rasters of different projections in a geoprocessing environment?  My understanding is that ArcMap will understand and project "on the fly" when 2 datasets have different projections and do the calculations correctly.  He is convinced that you must have all your datasets in the same projection to get accurate results.  My experience has not shown that to be the case, I've done map algebra and shown him that it does work, but he's not convinced of my results.  Please help us resolve this, its just been a giant waste of time and very contentious.