I have historical aerial photos that I have rectified and would like to add to an arcgis online map. I haven't been able to find a tutorial or walk-through to do this. Any ideas would be appreciated.
I would recommend this workflow to create a tile package from your raster, then upload it to ArcGIS Online. Once it is published in ArcGIS Online as a hosted tile layer, you will be able to add it to a Web Map.
Hope this helps,