Archived posting to the Leica Users Group, 2005/02/11
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Please point me in the direction of some explanation of what "APO" glass is then, if you know a url. I have heard of APO as an overall complete lens design specification many times but I have no knowledge that there is a particular APO glass. Frank On 11 Feb, 2005, at 16:07, JCB wrote: > I heard it from the mouth of Leitz, at Photokina, the year it was > introduced. > > JB > > > At 12:26 AM 2/11/2005, Frank Dernie wrote: > > >> AFAIK there is no such thing as "APO glass". To get APO performance a >> combination of elements of differing characteristics and curvature is >> required to cancel the fact that different colours diffract >> differently. The unusual partial dispersion glasses which this >> requires in at least one element are very expensive. Whether the 350 >> actually has these is debatable. The fact that it is v. sharp is well >> documented >> Frank >> >> >> On 11 Feb, 2005, at 01:30, SEUNG MIN LEE wrote: >> >> I have never heard that it had APO glass > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >