Archived posting to the Leica Users Group, 2009/10/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Thanks for this, as a 50 lover as I'm, I'll keep it! Saludos Lluis http://gallery.leica-users.org/v/luisrq/ http://photo.net/photos/lluisripoll http://lluisripollphotography.wordpress.com/ El 12/10/2009, a las 21:03, Seth Rosner escribi?: > Hello friends! > > I unsubscribed from the LUG months and months ago as I was traveling > and couldn't bear to return from a trip to 1500+ LUG emails. I > resubscribed to the digest and hadn't figured out how to respond to > a thread and inject my 2c. Happily, I just returned from the LHSA > annual meeting in Seattle that embraced a wonderful LUG dinner last > Friday at one of the best fish and seafood restaurants I've ever > experienced; with Mark and Henning and Greg and Tom + Tuulikki and > Peter and I'm certain to leave some good friends out so need to > leave out several. They told me how to respond to a thread and I > hope I have remembered the key to lugging-in. > > And as some of you know, I cannot leave my mitts off a Summicron > debate, especially when it involves Erwin Puts. I'm so out of it > that until I read this thread, I had not realized that he has left > being a Leica Camera tout and become a Zeiss/Cosina tout. > Fascinating. P.S. I learned in Seattle that marc small has left the > LUG so I am more or less safe since it was marc who several years > ago threatened me with a defamation action for having written > critically of Erwin's evaluations. > > So I took the time to look at Erwin's report on this Zeiss lens. > Here is what he writes about this lens in Phase 2: > > "Planar-T 2/50 ZM > "For several generations the Planar design has tried to challenge > the Summicron 50mm and never became as good. Now at last we have a > lens that equals the Summicron-M 50mm and is even a trace better in > the curvature of field area. The optical performance of the Planar > is simply as good as that what can be expected form the Leica > Summicron. The Double-Gauss design has been studied exhaustingly and > it is now possible to equal but not surpass the Summicron design as > long as you stay within the D-G limits. It is worth some study to > note that the curved elements of the Planar bring no significant > improvements in comparison to the many planar surfaces of the > current Summicron. > "This conclusion makes the claim of some Leica collectors, that the > current Summicron is a lesser design than the all-curved > predecessor, somewhat hollow." > > Many of you know that I am enamored of and have studied the 50/2 DR/ > Rigid Summicron exhaustively. In fact following the optical bench > tests of the 35/2 Summicron 8-glass, the pre-ASPH 35/2 Summicron and > the 35/2,8 Summaron that were the basis for my article in LHSA > Viewfinder, I have had the same optical bench tests done by optical > genius ;-) Roy Youman at Optikos Corporation on my 50/2 DR > Summicron, the vaunted ALPA Kern 50/1,9 Macro-Switar and the hugely > under-appreciated Leitz/Leica 60/2,8 Macro-Elmarit. For a forth- > coming Viewfinder article. > > First some basics. The DR/Rigid Summicron does indeed induce some > flare at f/2 and 2,8, created by the so-called "air-lenses" between > the first two and second two lens pairs. That flare disappears > somewhere between apertures f/2,8 and f/4. The 50 Summicron > introduced in 1969, 11817, was specifically designed for best > possible performance at the widest stops, ergo, to reduce flare and > at those stops, in flare-inducing photographics situations, it is an > improvement over the DR/Rigid. At f/4 and further stopped down, the > DR/Rigid's contrast = suppression of flare, is as good or better > than 11817 whose MTF charts are significantly worse than the DR/ > Rigid. The next - and current - 50 Summicron improved very > significantly on 11817 in both contrast and resolution but the > resolution of neither matches that of the DR/Rigid. Read carefully > here, I do not mean to suggest that the DR/Rigid will never flare at > the smaller stops, say f/8 and smaller. Only the later Leitz/Leica - > and other - lenses, the Noctiluxes being phenomenal examples, have > so remarkably suppressed flare and coma so that you can photograph > bright light sources within the frame and reproduce only the light > itself and no surrounding glow. All of the Summicrons - and the > Planars - will produce flare with light sources in the frame and in > contre jour, backlighted situations. > > Now, let's go back to Puts. As usual, Erwin mixes and matches to > lead to an incorrect inference, thinking that it will not be > noticed. He writes that the Planar "equals the Summicron-M and is > even a trace better in field curvature". He is comparing the Planar > to the current Summicron, NOT to the DR/Rigid. He could not possibly > make that statement about the DR/Rigid because that lens has a > remarkably flat field and absence of field curvature. Why? Because > it was designed not only for general photography but for close-up > work as well, where absence of field curvature is essential, ergo, > the famous viewfinder "goggles" or "bug-eyes". To Erwin's credit, he > acknowledges that "it is now possible to equal but not surpass the > [current] Summicron design as long as you stay within the D-G > limits". But he is not comparing it with the DR?Rigid. He nowhere in > this report claims that his now-beloved Zeiss 50/2 Planar equals, > let alone exceeds the DR/Rigid Summicron. You really have to read > this guy carefully; he's been bobbing and weaving like this in his > writing for years. > > But he then immediately seeks to confuse the issues again by > writing: "This conclusion makes the claim of some Leica collectors, > that the current Summicron is a lesser design than the all-curved > predecessor (the DR/Rigid), somewhat hollow." This sentence IS A > PERFECT NON-SEQUITUR. > > I have somewhere in my collection of Puts-isms a writing by him that > the current 50 Summicron introduced 5 plane surfaces in order to > reduce manufacturing costs (that would be both glass and assembly) > and in a different writing that when this is done, image quality is > not maintained. Understand, friends, that every lens, by any > manufacturer, is a compromise. The current 50 Summicron has better > overall optical performance than the DR/Rigid at the first two stops > IN HIGH FLARE SITUATIONS. Otherwise the DR/Rigid still delivers the > best overall optical perfomance available among these lenses. > > And of course even Erwin has often acknowledged that the build > quality of all of the Leitz lenses from the 1950's, '60's and very > early '70's has never since been equaled. > > At the same time, I have to say that the optical performance of the > new 50/1,4 Summilux-ASPH is absolutely astonishing, straight across > the board. The ONLY comments about it that I have heard or read that > were not entirely complimentary related to a certain edginess or > harshness that probably derives from its design purpose of > maintaining extraordinary high contrast at all stops and acrossd the > entire film/sensor plane. > > Now to Erwin's in installment 3: > > "Planar-T 2/50 ZM > "Wide open the lens shows excellent neutrality of colours with > amazingly good retention of fine colour hues. Very fine detail is > recorded with good clarity, but with less crispness than the Leica > counterpart. It shares with that lens the weak suppression of > secondary reflections, due to the reflections at the edges of the > rear mount. The background blur is on the harsh side. > The transition from the sharpness plane to the unsharpness regions > however is quite long, giving a fine impression of depth and > extension. The lens is especially good at recording detail in > extended shadow zones, when you take pictures at dusk or at night. > The background blur shows the major outlines of the subject shapes, > more sketching than drawing so to speak. Close up performance is > excellent from centre to edge without any vignetting and distortion. > The Planar wide open is a potent performer and at smaller apertures > becomes a master at reproducing with a life-like three > dimensionality, that was the hallmark of the G-version of the Planar > too." > > So let's analyze: > > "Very fine detail is recorded with good clarity, but with less > crispness than the Leica counterpart." > > In Erwin-speak, this means that the current Summicron-M has better > edge contrast than the Planar. It will be clearly inferior to the DR/ > Rigid except in the photo situations noted above. > > "It shares with that lens the weak suppression of secondary > reflections, due to the reflections at the edges of the rear mount. > The background blur is on the harsh side." > > First sentence is a comparison with the current not the DR > Summicron. The second sentence is an acknowledgement of bad bokeh. > > As a famous Irishman said in his allocution whilst standing upon an > English gallows: I am done. > > Seth > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information