Which Summicron
Which Summicron
I found this summary at a vendor's website(camerarepair.com) which clears up a lot of apocryphal information that has floated about on this forum and others. I hope it will be of assistance. You will note that this author indicates that the version 4 and the current version are not the same glass design. He notes that version 5 has the fourth optical design, which is not the same as version 4 which is the
third optical design. That is probably where the confusion came in with some people claiming that the fifth (current) version has the same optics as version 4
Like many of you I am trying to decide which version to buy, and this summary is very helpful, not in giving subjective opinion, which this interesting thread has tried to accomplish, but just discusses the design differences.
"..Not all Summicrons were created equal in optical quality. There has been a steady progression of Summicron optical design improvements over the decades. The first version introduced initially as a SM for the Leica IIIf and then in M mount approximately a year later is not as good as the one that quietly replaced it only 4 years later in 1957.
It has been relatively widely reported, do see page 135 of Dennis Laney' fine "Leica Collectors Guide" work, that there were three significant 50mm Summicron lens formulations. There were actually at least four. In 1957 Leitz/Leica introduced less than universally recognized but highly significant subtle changes to the original 7/6 (see our discussion of he screw mount version for why we do not call it a 7/4 as other sources do) formulation. To casual observation the 1957 embodiment looks unchanged but both glass curvature and glass composition formulation were altered significantly resulting in measurably better optical results.
Version 1: Serial numbers 1,112,000 through 1,709,000 for a total of approximately 113,300 in both SM and M mounts. Takes an E39 filter/attachment. Identical in lens formulation (7/6: 7 elements in 6 groups) and performance to the prior and concurrent SM version.
Version 2: SECOND SUMMICRON 7/6 LENS FORMULATION Improved optical formulation this is an extraordinarily sharp lens for its era. This is an identical formulation to that employed in the DR physical embodiment which is renown as legendarily sharp. Some would also be employed in proper serial numbered later SM lenses, both rigid and collapsible mount. Serial numbers 1,400,001 through 2,358,300. For total production of approximately 120,000 in all embodiments and mounts. !957-1968
Version 3: As Version 2 but DR physical embodiment. Simultaneous in time and overlapping serial numbers as well. Without the "EYES", the DR functions identically to version 2 focusing down to 1 meter. With the "EYES", which render a generalized parallax offset adjustment, the lens will crank out to a focal distance of only 48cm. Mechanically extremely complex, this lens represents what is widely regarded as an amazing high point in Leica's manufacturing capabilities. 1957-1968
Version 4: Third optical version, lens formulation evolves to 6/5 (six elements in five groups) with another set of improvements in optical quality. Glass incorporated is more physically stable (resistant to haze/deterioration) and yields sharper higher contrast results. Close focus to 70cm. Serial numbers 2,269,251-2,915,800. Takes E39 filter/accessory.
Version 5: (Fourth Optical Version) 1979 to Now. Serial numbers 2,909,101 to 3,XXX,XXX (some overlap at low end with previous version) 6/4 (Six elements in Four Groups) lens formulation. Characterized by manifold physical changes and finishes (Black Chrome, Silver Chrome, Titanium Tan, Black Paint, Platinum, Gold, etc.). Built-in hood since 1994. Close focus to 70cm. Takes E39 Filter/accessory..."