Archived posting to the Leica Users Group, 2000/08/28
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Mon, 28 August 2000, Paul Chefurka wrote: > > >From: telyt560@cswebmail.com [mailto:telyt560@cswebmail.com] > > > >It's one of the reasons I don't > >use mirror lenses. The effect was obvious to those who live > >by the long lens long before the word describing it was > >introduced to the english language. > > That's an interesting twist on the issue. When the short-lens hoi-polloi > talk about bokeh, we are usually referring to lenses in the 35 to 90mm > range. But the canonical (sorry) example of "bad bokeh" is mirror-lens > donuts. Are bokeh differences more visible in long teles even of normal > construction? > > The usual technique for using wide-aperture long teles is to just crank them > open and let the background mush out, so that the subject will "pop". It > seems to me that when used in this way, bokeh differences would not be > terribly visible. In the case of a bird sitting on a branch in a tree, shot > at f/8-11 or so, I can see that bokeh might be a significant issue. Tree > branches are notorious for demonstrating double-line bokeh. > > How much of a difference can you see between similar lens lines, Doug? > > Paul Paul, A good example is a comparison at full aperture of the 300mm f/4.5 Nikkor*ED and the 280mm f/4.8 Telyt-V. The Nikkor exhibits a harsh double-line bokeh that is almost like that of a mirror lens while the Telyt produces smooth washes of color. I read of another wildlife photographer (I don't recall his name) who uses a Nikkor*ED 400mm f/3.5 and a Leitz 400mm f/6.8 Telyt adapted to his Nikon F2. He said that while the f/3.5 aperture is very handy, the Nikkor is (I'm paraphrasing) too sharp, almost harsh, and if he were limited to one 400mm lens it would be the Telyt. He wrote this long before the bokeh concept was well understood and without definitive knowledge, I'm guessing it was the OOF rendition that made the Nikkor too harsh. That's how the 300mm ED appears to me. Doug Herr Birdman of Sacramento http://ourworld.compuserve.com/homepages/telyt - -------------------------------------------------- Visit the Northwestern Alumni Association portal page at http://www.nualumni.com to get free web-based e-mail and many other exciting features.