Archived posting to the Leica Users Group, 2000/11/23
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I wondered something different, since I had the impression that the APO configurations were for longer focal length lenses, where the difference in refractive angles for the differeing colors of light might be more noticable at the longer lengths- Thus a lens with a focal length of 180 or more mm might show the fringing effect more. I have always noticed it in cheap binoculars and cheap telescopes. I am sure that the APO enlarging lenses may make sens in focal lengths as short as 50mm because the conjugate distances- from film to lens and from lens to objective image are so close, but with a camera optic as short as 90MM would an APO formula make that much difference? Perhaps Erwin might enlighten us/me! I am really curious if an APO lens in say 50mm focal length would significant improve the color rendition if an image on the film? would the film itself be able to detect the minute amount if 'fringing'? Dan ( I am curious, fellow!) Post > > > Why is ther no Apo Summicron 90mm f/2 in silver chrome version? > >