Your meanderings have caused my brain to actually start working. Canon FD system, at one point, had some tiny plastic part used for manual diaphragm activation, did they not? Used for reversed lenses, as FD lenses not mounted revert to F5.6 diaphragm opening.
Why is it not possible to create such a part to mount temporarily in the back of K mount lenses which are mounted on the *ist line? Obviously the Canon part did not suffer any particular space limitations, given that it was intended for reversed lenses. Am I going mad? Kind regards Peter
