Question: are slr and dslr lenses interchangeable?
Answer: Any Canon "EF" lens made after 1987 will fit any Canon digital SLR, but none of the old “FD” mount lenses made before 1987 will fit. ... Any Canon EF DSLR lens will work perfectly with either system with the right Canon adaptor, while the smaller EF-S lenses can only fit EOS-M cameras through the "Mount adaptor EF-EOS M".