The Reproject function of the Image Analysis module should accept SpatialReference objects. It seems odd that it only can accept a python dictionary and the key is always 'wkid' as in {'wkid', 32611}. This only seems to make sense if there was a thought to except other types of ids as well like 'espg' or something. Also with the current design one can not use a custom spatial reference when using Reproject
