Archived posting to the Leica Users Group, 1999/09/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Marc James Small <msmall@roanoke.infi.net> wrote: >Erwin Puts and I have had some lengthy discussions about these [21, 24 & 28mm] designs, but I still don't know why Leica chose to use retrofocus designs for them. The elements of a retrofocus design are larger than those on a conventional wide-angle, so are easier to manufacture and mount. I'm always surprised by the difference in size between my 20mm f5.6 Russar and my 21mm f4 Super Angulon-R. The inner groups of the Russian lens must be very small. Perhaps Leitz thought in neccessary to move to retrofocus in order to get the speed of 28mm lenses to f2.8. Regards, Doug Richardson