Archived posting to the Leica Users Group, 2004/12/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Joseph, I beg most respectfully to differ with you on the contrast of the Kern 50/1, 9 Macro-Switar. You are quite right on its resolution, very comparable to the DR/Rigid Summicron. But its contrast cannot properly be called low. Unless one is speaking strictly of the lens wide open and at the far edge (18mm off-axis). At worst, if one were speaking generally, i.e. of the lens at various apretures and various points on the film plane, it is a medium contrast lens. Fuller explanation follows for those interested. While I agree with those who say "take photographs, look at the results and THEN decide if you like a lens" -out of curiosity last year I took five lenses to Cambridge Mass. to a company called Optikos Corporation that does optical design and engineering and has state-of-the-art test equipment. My interest was mainly to see how the 35/2,8 Summaron fared when compared with the first generation 8-element and the pre-ASPH 35/2 Summicrons. I have written an article on the results for these three lenses for LHSA's VIEWFINDER magazine that should appear in the next issue. I also took along and had Optikos test my 50/2 Rigid Summicron and Alpa Kern 50/1,9 Macro-Switar. While the contrast of both of these lenses at full aperture is lower than the current generation of Leica lenses, especially at the far edge (18mm off-axis), when stopped down to the medium apertures at which I usually shoot, the contrast of both is very, very close to that of the current 50/2 Summicron that Erwin has so often so praised. In fact, at medium apertures and some points on the image plane, both the DR/Rigid and the Switar slightly exceed the contrast of the current 50 Summicron! Incidentally, the 50/1,9 Macro-Switar was recomputed from its predecessor 50/1,8 in 1968 and my information is that it was indeed multi-coated. Amazing how much "information" is out there and how it becomes gospel. More astonishing still is the outstanding performance of this 36-year-old design and of my old favorite, the DR/Rigid that in two years will be celebrating its 50th birthday! My 36 year-old nephew was straight digital until 18 months ago and has now gotten into Leicas. First bought an M6TTL with a 35/1,4 ASPH and a Noctilux. Found the Nocti too heavy and bulky and sold it a few months ago for a new 50/1,4 Summilux ASPH that he loves and a new MP. I spoke with him yesterday to learn that a couple of weeks ago he bought a clean Dual-range from Stan Tamarkin and is astonished at the images he is producing. Bests, Seth LaK 9 ----- Original Message ----- From: "Joseph Yao" <joseph@yao.com> To: <lug@leica-users.org> Sent: Sunday, December 12, 2004 2:30 AM Subject: Re: [Leica] The only Leica I ever sold -- survey time > The lens is a Kern Macro Switar 50/1.9 from my Alpa SLR. I got an > Alpa-LTM > adapter from Retina House in Tokyo. Add one LTM-M adapter the lens goes > onto any M camera. > > This lens has amazing resolving power, but the contrast is low due to the > single coating. > > Joseph > > > on 11/12/04 11:24 pm, Slobodan Dimitrov at s.dimitrov@charter.net wrote: > >> Isn't that Alpa lens one of Tom's hybrids? >> S. Dimitrov > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >