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Dan Fromm
15-Sep-2004, 06:32
Last weekend I came by a pair of 240/9 G-Clarons in barrel. After I cleaned them up I looked at them and was surprised to see too few reflections for the lenses to be plasmat types.

Schneider's archive http://www.schneiderkreuznach.com/archiv/archiv.htm has two .pdfs on G-Clarons. The older, dated 7/76, describes a 6/2 double anastigmat type. The younger, dated 5/82, describes the well-known 6/4 plasmat type. A Google search found one reference to the older version, in one of Michael Gudzinowicz' lists of lenses.

Both types have about the same claimed coverage at f/9 and f/22, and both were offered in the same set of focal lengths.

My lenses serial numbers, according to te www.schneideroptics.com age of lenses page, were issued between 10/67 and 11/68. Each of my lenses' cells shows two strong and two faint reflections. 6/2, sure enough..

I shoot 2x3, so can't really test my new old lenses. Will someone please report on how well they perform? That Schneider changed designs makes me think that the older design must somehow fall short ... And does anyone know when the G-Claron was introduced?

Thanks,

Dan

Ernest Purdum
15-Sep-2004, 10:53
I have just been reading the Road & Track issue listing the 2005 cars. Most all of them list improvements over this years models, but I think many of the 2004 models would not be considered to "fall short".



It's a little confusing that Schneider changed the design without changing the model name. There was, however, no change in the purpose for which these lenses were intended. By introducing an airspace, the designer gained a little more opportunity for correction (no lens is perfect). Finding just what improvement may have resulted would probably be beyond the testing capabilities of most of us.



There may have been a different factor involved in the design change. The older G-Clarons were available in mechanical shutters only up to the 270mm focal length. The airspaced lenses fit into currently available Copal shutters all the way to the 355mm length. Shutter availability has had a huge influence in recent lens design.



The easiest way to tell the difference between the two models I know of is by the filter attachment size. Older lenses: 150 32.5. 210 40.5. 240 46. 270 49. 305 58. 355 67. Newer lenses: 150 35.5. 210 49. 240 52. 270 58. 305 67. 355 77. (All dimensions in millimeters.)



I don't think it's necessary to be very concerned whether or not a particular G-Claron is airspaced.

Steve Hamley
15-Sep-2004, 12:06
O.K., now I'm curious. How does the double anastigmat G-Claron differ from the double anastigmat Symmar that Glenn Evans has listed? Are they Dagor clones?

http://www.glennview.com/lens.htm

Steve

Dan Fromm
15-Sep-2004, 13:36
Ernest, thanks for the reply. I asked out of sincere curiousity -- I mean, I can't quite use mine on my little cameras, so can't ask them how good they are -- and because I have in mind to send them to auction and don't want to misrepresent them. Bad, bad Jim Galli's listings puff a little, as do the dread dagor77's, but neither strays into untruth. I want to avoid that territory too.

Steve, its a shame that Evans doesn't give his 360/6.8 Symmar's serial number. As is, the only clue to its age is that it isn't coated. It must be pre-WWII or early post-war. According to the Vade Mecum, plasmat type Symmars came in around 1952 and (not consistent?) that the f/6.8 dagor type Symmars were discontinued in 1954.. The earlier f/6.8 ones were dagor types that covered 80 degrees, according to the Vade Mecum.

My two lenses were made roughly 1967-8, are coated, and according to Schneider's archive are dagor clones. But they're f/9 and as slow dagors go don't have much coverage. If I read the documentation correctly -- my german is weak -- they cover 68 degrees at f/22. And the longest G-Claron is 355 mm; Evans' old Symmar is 360, not that there's any difference between 355 and 360.

Cheers,

Dan