I am not a professional, but I will say that it is not possible to use this Canon invention as a staffer (many honestly write nonsense) the lens is mainly for shooting landscapes, the architecture turns out great at a decent distance, otherwise it bends the buildings so much that it is impossible to straighten them (but this fact sometimes gives cool pictures) crop, I was not impressed, on the FF 5D MarkIII I sang here (I wanted to take a picture, try, learn, suffer and create) page=0 page=0 page=1 page=1 page=1