Archived posting to the Leica Users Group, 2002/12/01
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Thanks everybody for the response. I'll get the ELPRO in this case. - --- Doug Herr <telyt@earthlink.net> wrote: > on 12/1/02 7:39 AM, Henry Ting at > henryting10@yahoo.com wrote: > > > > > Can someone give me a lecture on the ELPRO > dedicated > > to the 100mm f2.8 APO macro ? > > > > I would imagine getting to a 1:1 ratio, a regular > > extender will give me better performance compared > with > > the ELPRO with the additional optics. What do I > gain > > with the ELPRO ? > > > > The 100 APO's focussing mechanism is somewhere > between front-group focussing > and internal focus. The lens is optimized for each > focussing distance by > shifting some elements relative to others as the > focussing ring is turned. > Extension rings can be used but since they change > the distance from the rear > element to the film plane, all the fancy optimizing > mechanism would be for > naught. The ELPRO allows closer focus without > losing the advantages of the > optimizing tricks, so in this case, the 100 with the > ELPRO designed > specifically for the 100 APO will out-perform the > lens alone with extension > tubes. > > Doug Herr > Birdman of Sacramento > http://www.wildlightphoto.com > > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html