Archived posting to the Leica Users Group, 1996/11/03
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 09:33 AM 11/3/96 +0100, Erwin Puts wrote: > >These are thought provoking remarks indeed. Which bench-tests are you >referring to. There are so many. And what Zeiss lenses are you pointing at. >Zeiss by the way is since the early seventies actively promoting this >strategy of design relaxation, meaning that a lens design should be >optimised for practical perposes, not bench-test results. Read the document >by Dr Kammerer of Zeiss: "Wann sind Qualit=E4tssteigerungen bei >photographischen Objektiven sinnvoll" (Wenn does it makes sense to improve >on the quality of photographic optics). In this booklet the factors of >human perception are fully accounted for. The late Dr Joachim Kaemmerer was a Voigtlander carryover, one of the last heirs to the rich tradition of that fine house, brought to Zeiss when they purchased Voigtlander in the '50's. He was active in the development of the final series of Contarex optics and went on to head up Optical Design at Zeiss Oberkochen in the '80's. He was an active supporter of Zeiss Historica and is sadly missed. >Would you mind elaborating on this simple trick of Berek. How can you >design a lens to produce a final image that in the eyes of the observer >seems to be of higher quality than it actually is. Here we' re touching on >a very important subject, viz, the psychology of perception. There is >clearly a difference between the functioning of human perception and the >cool registration of measuring instruments. Please see my many, many other posts on this topic. There is no gameplaying with perception: emphasize the fuzziness of the out-of-focus image, and the in-focus part seems sharper. This is hardly rocket science, nor is it terribly challenging. >This might explain the difference in the opinions of so many of the members >of this LUG (who ara all keen observers of the Leica world) on the >different aspects of Leica lenses. It seems strange that the same lens ( >for instance the Summilux 1.4/75) has been described as having a high >contrast image at full aperture and as having a low contrast image. In such >a divergence of opinions, perception must play its part. But I am not sure >which part. I believe that only ONE poster stated that a SINGLE 1.4/75 had low contrast and suggested that this SINGLE lens may have been defective. =20 Marc msmall@roanoke.infi.net FAX: +540/343-7315 Cha robh bas fir gun ghras fir!