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Uusilehto
14-Jun-2007, 08:52
I received today three Dagors: 12.5cm f/6.8, 180/6.8 and the most exciting one, a Weitwinkel-Dagor 150/9

The other ones aren't really that exciting so I'll concentrate on the Weitwinkel one.

The only other Weitwinkel-Dagor marked lens I've seen is a 210mm f/9 Weitwinkel Dagor. The only mention I've found of this lens is on an eBay auction #110136534579 . It is indeed VERY similar to the one I purchased with the exception of being in a barrel.

I know there is a Zeiss line of Dagors with an aperture of f/9 but this says C.P Goerz Berlin. Could this be a prototype Goerz-designed wide-angle Dagor made just before the merging to Zeiss?

One thing about this lens annoys me a whole lot. It didn't come with a retaining ring. It's the same diameter as a #1 shutter (about 39mm) but with a slightly coarser pitch. A #1 retaining ring turns in about 2 turns before stopping. With the exception of the retaining ring, everything else is just fine. Lens elements are bright and shiny, speeds are accurate within half a stop and the aperture blades are clean.

Considering its apparent rareness, how much would it be worth? I don't have a 8x10 camera and even if I did, I probably wouldn't want to use this one on it. Besides, I'm not really into collectibles. I prefer to actually use my gear.

ANY opinions on this one are greatly appreciated. I tried searching for information but nothing turned up. Some mentions of a Goerz designed wide-angle Dagor but nothing beyond that.

Here's a picture of the lens. The first is just a shot with the other ones in it.
http://www.kolumbus.fi/uusilehto/img/dagor/dagorit.jpg

http://www.kolumbus.fi/uusilehto/img/dagor/wwdagor.jpg

Jack Flesher
14-Jun-2007, 09:01
Weitwinkle = "Wideangle". It is my understanding this would be the predecessor to the more commonly marked "W.A." f9 Dagor. Later versions were single-coated. Stopped down, regular dagors cover about 80 degrees while the wideangle about 100. This 150 should cover 8x10 with a bit of room when stopped down past f22.

PS: It also looks like the cells are in very good shape, so even uncoated, this one should deliver pretty good image quality too -- congratulations!

Uusilehto
14-Jun-2007, 09:09
It is my understanding this would be the predecessor to the more commonly marked "W.A." f9 Dagor.
Yes, that was more or less what I concluded from my research. The thing that strikes as odd to me is that it is indeed from the C.P. Goerz Berlin era instead of being a Zeiss branded one.


PS: It also looks like the cells are in very good shape, so even uncoated, this one should deliver pretty good image quality too -- congratulations!
Thank you. I am trying to get a hold of an 8x10 camera for a few test shots. It's rainy today but I'll see what I can do with the 4x5 tomorrow.

koidr
14-Jun-2007, 10:01
Maybe you could hele me i got a lens with a 4x5 i bought is says w.a.dagor 3 5/8 F-8 c.p. goerz am. opt. co. #805020. Is this a good lens and will it cover 4x5. If you could hlep that would be great.

Thanks Dave

Jack Flesher
14-Jun-2007, 10:06
Maybe you could hele me i got a lens with a 4x5 i bought is says w.a.dagor 3 5/8 F-8 c.p. goerz am. opt. co. #805020. Is this a good lens and will it cover 4x5. If you could hlep that would be great.

Thanks Dave

Yes, it will cover 4x5 and is of similar performance to the 90 f6.8 angulon.

Sven Schroder
14-Jun-2007, 10:38
Hi all

Looking at it the Pictured lens in question, it is very similar to the Zeiss issue wide angle dagors of which I have 75mm 125mm and (180mm on the way).It seems to have been made at some crossover point in the merger and is different to the Goerz Am opt
F8 Issue which aparently has less coverage? and have minor differences in construction.

Regards
Sven

Jan Pedersen
14-Jun-2007, 12:41
Just sitting here with open mouth, are you buying Dagors in bulk these days?:eek:

Uusilehto
14-Jun-2007, 12:50
Just sitting here with open mouth, are you buying Dagors in bulk these days?:eek:

Not really. Found them on a local auction site 15€ each. Obviously, I snatched them all along with a universal iris diaphragm lens mount (about 85mm max opening) for 60€.

Reminds me of the time when I traded in a boring 2€ flea-market figurine (although actually worth about 80€) for a 2001 CLA'd Leica IIIf RD + 50/1.5 Summarit. Sold the Leica kit for 650€ and bought myself a Canon 1D (need a back-up DSLR for actual work). Life is good.

Uusilehto
15-Jun-2007, 05:24
Something interesting came up.
I have been successful in finding various mechanical patents in the past and figured that the lens just might be listed in the patent archives.
A bit of searching on the Google patent search turned out a 1927 patent filed by Franz Urban (of C.P. Goerz) on 21th of December, 1923.

I have the patent mirrored on my FTP, here: http://www.kolumbus.fi/uusilehto/dagorpatent.pdf

I believe it to be the same lens. Aperture ratio of 1:9, 100 degree AOV and a 6/2 double-anastigmat construction.

Maybe they couldn't get it into mass production before Zeiss merged the company?

Rider
15-Jun-2007, 05:52
Nice find! Let's see some pictures.

Pete Roody
15-Jun-2007, 07:48
Something interesting came up.
I have been successful in finding various mechanical patents in the past and figured that the lens just might be listed in the patent archives.
A bit of searching on the Google patent search turned out a 1927 patent filed by Franz Urban (of C.P. Goerz) on 21th of December, 1923.

I have the patent mirrored on my FTP, here: http://www.kolumbus.fi/uusilehto/dagorpatent.pdf

I believe it to be the same lens. Aperture ratio of 1:9, 100 degree AOV and a 6/2 double-anastigmat construction.

Maybe they couldn't get it into mass production before Zeiss merged the company?

Maybe you are correct that this is the Patent for the F9 Goerz Dagors. This is the design that Zeiss probably used also. I have a few of these lenses from 75mm to 210mm and they are great performers. I don't know if the American Goerz company used this exact design since they were a seperate firm (from Goerz in Germany) at that time and the American wa dagors had a maximum aperture of F8.

It looks like the patent gives detailed information regarding the design of the lens. Maybe someone out there will try to re-manufacture them. A new 300mm design would be nice.

Uusilehto
15-Jun-2007, 08:03
I have a few of these lenses from 75mm to 210mm and they are great performers.

You mean you have C.P. Goerz marked f/9 Weitwinkel Dagors or the Zeiss versions? If you do indeed have the C.P Goerz versions, could you possibly post a few pictures of them? There doesn't seem to be a lot (any) information on these particular lenses on the internet.


I don't know if the American Goerz company used this exact design since they were a seperate firm (from Goerz in Germany) at that time and the American wa dagors had a maximum aperture of F8.

As I understand it, the American f/8 design is considerably different compared to the f/8 Zeiss version. Supposedly it has less coverage.

Pete Roody
15-Jun-2007, 08:15
You mean you have C.P. Goerz marked f/9 Weitwinkel Dagors or the Zeiss versions? If you do indeed have the C.P Goerz versions, could you possibly post a few pictures of them? There doesn't seem to be a lot (any) information on these particular lenses on the internet.



As I understand it, the American f/8 design is considerably different compared to the f/8 Zeiss version. Supposedly it has less coverage.

I have the more common Zeiss F9 dagors.

Pete Roody
15-Jun-2007, 08:22
You mean you have C.P. Goerz marked f/9 Weitwinkel Dagors or the Zeiss versions? If you do indeed have the C.P Goerz versions, could you possibly post a few pictures of them? There doesn't seem to be a lot (any) information on these particular lenses on the internet.



As I understand it, the American f/8 design is considerably different compared to the f/8 Zeiss version. Supposedly it has less coverage.

Vade Mecum has info on the F9 Goerz Dagors:

"Wide Angle Dagor f9.0 This was a later lens and was listed in 1924 in 75mm for 4.25x3.25in, 100mm for 6.5x4.75in, 125mm for 8.5x6.5in, 150mm for 9x7in, 180mm for 10x8in, 210mm for 12x10in, 240mm for 15x12in all for stopped down use (Goe014) This lens can cover at least 100, and 150mm is actually useful on 10x8in when stopped right down. (There is a patent for an f9 wide angle anastigmat of this type to Goerz (Brit Pat. 209,093 of 1922), using a low R.I. meniscus with a high R.I. flint for the biconcave and baryta flint for the external biconvex lens. The design was aimed at reducing astigmatism at wide angles.) It seems to be the precursor of some of the USA Golden Dagors, from the Goerz USA company. It was 'new' in the Photograms 1924 advert. ie was a 1923 introduction, and may have been a 1920's reinvention of the f11 above. The usual version found in the UK is the 125mm, probably sold for 1/1plate, and seen at No597,53x, where 2 lenses of nearly the same number are known, probably from the same shipment. The 125mm covers 1/1plate but is very tight on 10x8in unless indoors, when the bellows are a bit extended and then it may just cover. Later versions are in rimset Compur shutters and made by Zeiss- Dagor f9 was one of the few Goerz lenses Zeiss continued after the amalgamation. The old stock of Dagors f6.8 were sold off to Burke and James and overhung the market for many years, being referred to in USA as Berlin-Dagors to distinguish them from the USA products.

Measurements suggest the external curves of the f9 wide angle are slightly deeper than the f6.8 but these are not really strikingly different. What is different is that the outer diameter of the f9 is some 10% bigger than the f6.8 equivalent- and the inner glass diameter is reduced to near 25% less than the f6.8 This will improve edge illumination and the limit on the aperture will improve the sharpness and contrast to some extent. What must be about the last f9.0 Dagors seem not to have been marked as "Wide Angle" and were noted from Zeiss Jena at No2,802,51x in stereo pairs, possibly for air survey use in the WW2 as this seems to be a 1942 serial number. They are not coated, and in non-iris barrel mount."

Uusilehto
15-Jun-2007, 08:24
Wow, that's a lot of info. It says that the lens is from 1923 (pre-merge and consistent with the patent) but then it mentions Zeiss Jena and "wide angle dagor". Did C.P. Goerz Berlin mark any of their lenses in English?

It mentions the Goerz patent only as a sidenote, so I'm not sure whether or not this is a description of the Goerz version or the Jena version. Confusing but then.. English is not my native language.

EDIT: After reading it again, I get the idea that it was a fairly limited production model from 1924 to when it was discontinued by Zeiss after the merger. It was then re-introduced as the Zeiss Goerz-Dagor f/9. Correct, no?

EDIT2: What exactly is this Vade Mecum? I hear it from time to time on this forum. Some kind of a lens database?

Pete Roody
15-Jun-2007, 09:28
Wow, that's a lot of info. It says that the lens is from 1923 (pre-merge and consistent with the patent) but then it mentions Zeiss Jena and "wide angle dagor". Did C.P. Goerz Berlin mark any of their lenses in English?

It mentions the Goerz patent only as a sidenote, so I'm not sure whether or not this is a description of the Goerz version or the Jena version. Confusing but then.. English is not my native language.

EDIT: After reading it again, I get the idea that it was a fairly limited production model from 1924 to when it was discontinued by Zeiss after the merger. It was then re-introduced as the Zeiss Goerz-Dagor f/9. Correct, no?

Yes, this is correct.

EDIT2: What exactly is this Vade Mecum? I hear it from time to time on this forum. Some kind of a lens database?

Vade Mecum is a rambling database created by a lens collector(s). Do a search on eBay. There is a guy who sells a downloadable version. It is not totally accurate but is an interesting read if you like older lenses.

Uusilehto
21-Jun-2007, 06:23
And the scans are done.

A little info on the weitwinkel-Dagor first. I noticed that in addition to the serial number at the edge of the Compur shutter, there is also a stamped serial number at the back of the shutter. This serial number is identical to the one on the lens. Interesting.

I am going backpacking with the Sinar on Saturday so I needed to put these little lenses to a little test anyway. I was quite surprised by the 125/6.8. I expected the corners to be mush but no. Apologies for the miserably failed perspective correction. I was in a hurry and missed it somehow.

Now, for the wide-Dagor I tried to find a subject that required a bit more movements. 4.5cm or so of rise should be enough. I was shocked to see the contrast loss bleeding from the highlights. After a careful re-check, I noticed to my horror that there is separation between the two front elements. Oh, the horror, the horror.

Next week, when I'm less busy, I'll try to do a detail-rich experiment with the 150mm weitwinkel-Dagor where the camera back has been moved so that it's basically in the same position as a 4x5" crop out of an 8x10" corner would be. Just to see if it really does cover 8x10 with acceptable resolution.

I didn't try the 180/6.8 because I more or less know that it's a good performer.

First, the less interesting 12.5cm Dagor:

http://www.kolumbus.fi/uusilehto/img/4x5/125dagor.jpg

And then the 15cm f/9 Dagor

http://www.kolumbus.fi/uusilehto/img/4x5/150dagor.jpg