On 10/2/07, Collin R Brendemuehl, discombobulated, unleashed: >I'm about to propose a heresy. >Nothing that G K Chesterton or Cornelius Plantinga would write about, >but heresy never the less. > >It's come to my attention that a lot of old FD mount lenses are going >pretty cheap. And the breech system attached to the >outside of the body, not really internal .... soo >Remove the mount from an old Canon body and fuse it to a screw-mount >adapter and voila -- a Canon-> Pentax adapter. >Then just remove the aperture coupling from the lens. > >Next time I find an old FD body and lens that's worthless, I may give >it a try. (I just saw an old Canon 300/4.5 going >for a modest price and this idea entered my mind ...) > >Yes, it is heresy. But can I be cleansed? Somebody help me ... I've fallen. >(Or is this a heresy/project better suited to Cotty?)
I'm here. Pentax K register distance is 45.46mm Canon FD register distance is 42mm This means that to alter an FD lens to fit a K mount camera (without using an adapter containing an optical element to correct for infinity focus) you would have to remove over 3 and a half mil from the back of the FD lens flange. If you're going to use a 42mm threaded adapter, then add the thickness of the adapter to that. Might be problems in that there's not enough room on the back of the FD lens before problems start in terms of aperture ring etc. You may or may not have problems with the rear element of the lens not clearing the mirror. I don't have an FD to look at, but where there's a will, there's a way. I have some links on the bottom of this page that might be of further interest: <http://www.cottysnaps.com/snaps/mods/details.html> It's a big job but as an engineering exercise, viable, if expensive. Of course, as a hobbyist, cost is not justifiable so go to it! -- Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=====| http://www.cottysnaps.com _____________________________ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
