Archived posting to the Leica Users Group, 1998/05/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Yes - sorry, I could not resist. Raimo - ---------- > From: Bryan Willman <bryanwi@seanet.com> > To: leica-users@mejac.palo-alto.ca.us > Subject: Re: [Leica] Retrofocus. was sharpness discussion > Date: 26. toukokuuta 1998 4:34 >=20 > 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. >=20 > A true telephoto (as opposed to mearly a long lens) means one in whic= h the lens is physically shorter than it's focal length. (Which also mea= ns it can focus to infinity without having to draw the extension > of its focal length, which turns out to be a big deal > for view cameras, of a= ll things.) >=20 > bmw >=20 > -----Original Message----- > From: Raimo Korhonen <raimo.korhonen@pp2.inet.fi> > To: leica-users@mejac.palo-alto.ca.us <leica-users@mejac.palo-alto.ca= .us> > Date: Monday, May 25, 1998 11:56 AM > Subject: Re: [Leica] Retrofocus. was sharpness discussion >=20 > Elementary - it=B4s an inverted telephoto design. Raimo ;-) >=20 > ---------- > > From: Mark <mark@steinberg.net> > > To: leica-users@mejac.palo-alto.ca.us > > Subject: [Leica] Retrofocus. was sharpness discussion > > Date: 25. toukokuuta 1998 18:02 > > > > i have to ask, what is "Retrofocus" ? > > > > m >=20