to moze tak...
sama rozpiska mocowania, jak najbardziej publiczna:
Canon EF lens mount - Wikipedia, the free encyclopedia
ale oczywiscie:
za: Canon EOS Beginners' FAQ III - LensesThe only third-party maker of EF-compatible lenses with no major compatibility problems so far is Tamron. Some people have suggested that this is because Tamron have licensed official lens protocol data from Canon, but Canon USAâs Chuck Westfall has stated repeatedly in public fora that Canon have never licensed their lens mount protocol to any other manufacturer.