I have found a source of NOS Canon FD 28mm f2.8 lenses, ideal for reversing onto my EM1 Reluctant as I am to cite other forums, I came across this...... http://www.dpreview.com/forums/post/35014905 I've been messing about with macro and reversing for well over 50 years but I cannot come to terms with what this guy is proposing.....an adaptor between the body and the reversing ring. If the adaptor is required, it does nothing other than act as a spacer/stand-off. Mind you, his results do look impressive. However, I have never reversed a Canon on M4/3 before. Your opinion Gentlemen/Macro Nuts is sought.