Schneider-Kreuznach G-Claron 150mm f11

[xkaes]

From time to time I see a 150mm f/11 G-Claron offered for sale. In every case a photo shows that the front lens cell is clearly engraved with f/11, not f/9. There's one offered on eBay right now with a serial number (11693xxx) that places its manufacture around 1971.

My Nov 1967, Sep 1976, May 1982, and Aug 1998 Schneider literature PDFs all list the 150mm as an f/9 lens. The G-Claron-WA was an f/11 lens, but it was offerered only in 210mm, 240mm, and 270mm as far as I know (I only have the May 1982 info sheet on these) and in every image I've seen it had the letters "WA" in its markings.

Does anyone know more about these f/11 150mm G-Clarons?

So why are we having the conversation?

[lassethomas]

There never was a 150/11 WA G-Claron. 210, 240 and 270. That's all.

Well, yes agreed.
But there are obviously dagor type G-Claron 150mm lenses engraved as "1:11/150" on the front cell. In a different casing compared with the f/9 version and with no filter thread (got one). see post #7.
Even though they're not mentioned in any still existing literature.
Whether they really are f11 or f9 is another matter.

Never got round the try mine out. It's really not the most pressing question mark to straighten.

[lassethomas]

So why are we having the conversation?

It's a sort of a mystery. Not an important or especially thrilling one. But mysteries are always intriguing, aren't they?

[Dan Fromm]

So why are we having the conversation?

Anomalies prompt questions. I think that the question you quoted in post #31 above answered your question.

[Sal Santamaura]

....there are obviously dagor type G-Claron 150mm lenses engraved as "1:11/150" on the front cell. In a different casing compared with the f/9 version and with no filter thread (got one). see post #7.
Even though they're not mentioned in any still existing literature.
Whether they really are f11 or f9 is another matter...

Perhaps the engraving refers to a magnification ratio rather than maximum aperture? Maybe that's why the notation isn't "f/11."

[Dan Fromm]

Perhaps the engraving refers to a magnification ratio rather than maximum aperture? Maybe that's why the notation isn't "f/11."

1:some other number has often been used to indicate relative aperture. In this case, 1:11 means f/11.

[Paul Ewins]

I've checked the production lists (Hartmut Thiele's "Grosses Fabrikationbusch Schneider-Kreuznach Band II") and there are multiple batches for both a 150/9 and 150/11 G-Claron produced in the 1970/71 period. These were regular sizes batches of 600 - 1000 lenses at a time with no mention of them being special orders. There is also quite a bit of prototype work going on with G-Clarons at this stage, and the first mention of the 150/11 is a batch of three prototypes on 6 July 1970. At a guess 1970/71 is the changeover point from the Dagor to the Plasmat and what we see are the last of the 150/9 Dagors alongside a 150/11 Plasmat fitted into the Dagor barrels. This then gives way to 150/9 Plasmats in a new barrel which becomes the standard from this point. Again, this is a guess.

FWIW the first mention of a WA Dagor is a prototype 270/6.3 G-Claron WA in September 1972 and then a 210/11 WA Claron in August 1973.

[xkaes]

I've checked the production lists (Hartmut Thiele's "Grosses Fabrikationbusch Schneider-Kreuznach Band II") and there are multiple batches for both a 150/9 and 150/11 G-Claron produced in the 1970/71 period. These were regular sizes batches of 600 - 1000 lenses at a time with no mention of them being special orders.

And there are some other examples of lenses that appeared in small numbers during the evolution of an old line to a new line -- and the numbers produced were so limited that they never made it into the official advertising brochures. With Fuji this apparently happened between some of the SW lenses switching to the NSW series, and some of the W lenses moving to the NW line-up. And then the "So what IS this lens?" questions pop up.

[Drew Wiley]

I've never seen one of those, but it's probably no error. There were different series of G-Clarons, depending on intended application, some in barrel for limited graphics applications, such as small "stat" copy cameras needing a wide angle lens. The f/9 plasmat design GC's equipped in shutter are wonderful all the way from closeup to infinity; but I'd personally avoid the WA for general photographic usage.

[arri]

The G-Claron 11/150mm is made of four elements in two cemented groups, similar to the Zeiss Protar, not the Doppel Protar, or the Rodenstock Perigon.
The different ist that the G-Claron is 100% symmetrical.
Angle of view is around 85°.
Very sharp when stoped down to f/22
Like all G-Claron it is apochromatic cerrected.
Guess Schneider tried to offer a wide angle lens for reprographic usage. The less speed is not a problem in reprographic usage.

The following six element G-Cs and G-Cs WA with air spaced elements are better corrected for colour work, upcoming more and more end of the 1960th.
I guess that is the reason why the fully cemented 11/150mm when only made in very small charges.

This is a well known process, Schneider changed the Angulon to the Super Angulon and the 6.8 Symmar to the 5.6 Symmar in the same way, both lens designs were renewed with airspaced elements.

I have a G-Claron 11/150 in use and I removed the glass elements for a cleaning, that´s why I´am knowing it is a four element lens and the reason is like I descriped.

It is a very interessting lens, I have a small Schneider collection with some prototypes and this is a gem of it.