Archived posting to the Leica Users Group, 1998/05/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 08:23 PM 5/25/98 , you wrote: >At 07:34 PM 5/25/98 -0700, Bryan Willman wrote: >>The real point here is that Retrofocus lens is >>physically longer than its focal length. So, >>a 21mm for an M camera must be retrofocus, >>since you can't fit the nodal point within 21mm >>of the film plane. > > >It's the other way around. A 21mm lens for an rf camera, such as the M, >CAN be non-retrofocus, as you can design it readily so that the rear >element is easily within 21mm of the shutter curtain/focal plane Rear nodal point, not rear element. In the case of the M6, you are precluded from putting stuff too close to the film plane by the design of the metering system. - -Paul