I have georeferenced rasters in QGIS (2.18). We assigned a coordinate system to the image: EPSG 26917, which is NAD83 Zone 17N. When i then bring this image into ESRI, the coordinate system is redefined as some custom projection called "UTM_Zone_17_Northern_Hemisphere" with a made up GCS but which otherwise matches the standard UTM 17 in ESRI. What i can't understand is why it's doing this - the ID for the system is correct in QGIS, but ESRI won't accept it - even though ESRI also uses EPSG ID's and NAD83 17N is the same in both programs. Because the systems don't match, i can't then edit the rasters as i need to. I have to keep this bogus projection and re-project all my images as i go.