Is there a web site which has a reproduction of that article? Bill From: Edward Meyers <aghalidebw@xxxxxxxxx> Reply-To: <rollei_list@xxxxxxxxxxxxx> Date: Sun, 23 Oct 2011 17:43:20 -0400 To: <rollei_list@xxxxxxxxxxxxx> Subject: [rollei_list] Re: Sweet spot: f8/f11? Burt Keppler hated to be called Herbert. As far as the Rollieflex lenses are concerned, I am the guy who tested them. What I remember 5.6 was the magic f number. I believe the results of the tests that you refer to are based on resolution. Ed Meyers, former technical editor of Modern Photography in 1960s. On Sun, Oct 23, 2011 at 8:02 AM, Marc James Small <marcsmall@xxxxxxxxxxx> wrote: > At 07:28 AM 10/23/2011, CarlosMFreaza wrote: >> >2011/10/22 Bob James <starboy0@xxxxxxxxxxxxx>: >>> >> So for the TLR 2.8f which aperture allows the lens to perform at its >> >best? f8, f11? >> > >> >It's interesting to note while most standard lenses have the best >> >performance between f8 and f11, Planars and Xenotars 2.8/80 have the >> >best performance at f16 (both lenses, I agree with this test following >> >my experience with the Xenotar 2.8/80) according some "Modern >> >Photography" magazine tests (Herbert Kaplan) made when cameras and >> >lenses were brand new ( 2.8F, I posted the link last August). BTW, you >> >could have your own preferences according the photography you are >> >doing; I like my Xenotar at f5.6 very much for portraits, it offers a >> >very right sharpness for the subject and a good separation regarding >> >the background and the "bokeh" is from acceptable to good in general >> >for this f/stop. >> >In the other hand, the best performance for Planar and Xenotar 3.5/75 >> >is at f/11 according the same tests. > > Carlos > > I would approach any camera magazine test of lens quality with a bit of > caution. Burt Keppler was a good commentator but, then, he was also a man of > pronounced biases. > > The Carl Zeiss MTF data seems to set out that the 2.8/80 Planar used in the GX > and FX cameras achieves its best performance from f/5.6. I am not aware of > similar scientific tests done on the earlier versions of this lens or on the > Xenotar. In my personal experience, both lenses as used in the 2.8F and > earlier cameras peak from f/8 but, again, my own experience is hardly any more > a scientific test than were the musings of Burt Keppler. > > Marc > > > msmall@xxxxxxxxxxxx > Cha robh bàs fir gun ghràs fir! > > > --- > Rollei List > > - Post to rollei_list@xxxxxxxxxxxxx > > - Subscribe at rollei_list-request@xxxxxxxxxxxxx > <mailto:rollei_list-request@xxxxxxxxxxxxx> with 'subscribe' in the subject > field OR by logging into www.freelists.org <//www.freelists.org/> > > - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx > <mailto:rollei_list-request@xxxxxxxxxxxxx> with 'unsubscribe' in the subject > field OR by logging into www.freelists.org <//www.freelists.org/> > > - Online, searchable archives are available at > //www.freelists.org/archives/rollei_list > <//www.freelists.org/archives/rollei_list> >