Archived posting to the Leica Users Group, 2008/06/11
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Good morning, Philip, This is an interesting discussion. I believe there is another problem adapting such a lens to an M Leica, i.e. the quite narrow depth of field of a 180mm lens. I recollect in the 1960's, Leitz experimenting with their newly-introduced 180mm f/2,8 Elmarit-R and fabricating a focusing mount analagous to their 135/2,8 Elmarit-M with attached viewfinder. They never put this version of the lens into production because even with the viewfinder magnification of the image, the rangefinder base was too narrow to give sufficiently accurate focusing. And of course you're right, zone focus woould be hopeless with this long a lens. Seth ----- Original Message ----- From: "Philip Forrest" <photo.forrest@earthlink.net> To: "Leica Users Group" <lug@leica-users.org> Sent: Wednesday, June 11, 2008 1:24 AM Subject: Re: [Leica] Favorite Non-Leica-Leica Lens? > Zone focusing with such a lens as a 180mm f/2.8 Nikkor would be next to > impossible without a tripod, measuring tape and an accurately labeled > lens barrel (and some faith!) Novoflex made the adapter without RF > coupling because each focal length would need its own adapter as they > have different rates of focus. I'm currently working on a simple > version of an M42-LTM RF coupled adapter for the Takumar 50mm f/1.4. The > rate of movement of the Takumar is within .20 mm of both of my other > two 50mm lenses for Leica. Adapting a simple push-rod RF cam actuator > inside the adapter is pretty simple. A few hours with a dremel, some > pliers, sore hands, maybe a little JB weld and the adapter would be > done. > Creating such a beast for a very long lens would be more difficult > because of the variable rate of focus. An intermediate cam would be > necessary, but not impossible. Not something for my dremel tool and a > weekend. That's for CAD CAM machinery. If I only had access to a mill > like that, I'd be making adapters for all sorts of lenses. > > Phil Forrest > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >