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View Full Version : Dagor "series" Whats the diff?



John Kasaian
29-Apr-2005, 16:09
I've heard of series II, series III and series IV Goerz Dagors and I was curious: What is the difference between them? I know one is supposed to be a wider lens than the others, but other than that, 'm clueless. Anybody here know?

Ernest Purdum
29-Apr-2005, 19:36
There seems to be some confusion here. "Double Anastigmat Goerz, Series III" was the original designation for the Dagor. In 1904 the acronym "Dagor" was adopted. I don't believe other "Series" designations werre ever applied to the Dagor, but Goerz series II was an elaborate convertible type, while Series IV was a process lens.

The major design variation to the f6.8 or f7.7 Dagors is the "Wide Angle Dagor". The original German-made lenses had a maximum aperture of f9. In the U.S.A. this was increased to f8. Besides being slower, the proportions of the inner and outer elements were different so as to achieve better illumination in the corners. I've never seen a Series number used in regards to the wide angle type, which has about thirteen degrees more angular coverage than the normal type.

Maybe somebody was using an unofficial designation ofl his own to differentiate between Dagors made at different times and in different places.

John Kasaian
29-Apr-2005, 19:51
Thanks Ernest! Is the process version very different from the f6.8 or f7.7 series II?

Tracy Storer
29-Apr-2005, 20:50
I have owned two Series IV Double Anastigmats, a 30" (sold) and a 19." I also have a 19" Series III. Coverage of both 19" lenses is good for 20x24. (as was the 30"....sellers remorse, alas)
Best,
Tracy

Ernest Purdum
29-Apr-2005, 21:30
I'm sorry, I know very little about the process lenses, except that they were made in f11 aperture and were unusual amongst process lenses of the time in that in Dagor fashion they covered a wide angle. At the time, most process work was done on huge horizontal cameras, so a rather narrow view was quite acceptable

Since Tracy has had two of these quite uncommon lenses, perhaps he can provide more information..

Tracy Storer
30-Apr-2005, 10:32
Aside from being f/11 instead of 6.8 or 7.7, I don't think there is much difference. I have a copy of an old Goerz catalog which states infinity coverage the same as Series III. One odd note, my 30" was 8/2 construction instead of 6/2. But it had a Burke and James sticker on it, so...who knows? It performed well.
The 19" is 6/2.

David A. Goldfarb
30-Apr-2005, 13:15
Was the lens with the B&J sticker coated? B&J did some aftermarket coating of older lenses and put their sticker on them. I have a 210/3.5 Xenar like this--the lens is older than lens coatings, but it's coated and has a B&J sticker.

Tracy Storer
30-Apr-2005, 13:50
Yes, it was coated, and I suspect it was assembled from bits and pieces as a lot of the B+J glass was. It had LOTS of air bubbles in the elements which probably would not have passed muster for a genuine Goerz/AO lens.

Ole Tjugen
30-Apr-2005, 14:33
David, is that a "Typ D" Xenar?

I know this is getting way off topic, but it is vaguely related: "Typ D" Xenar is not a Tessar lens...

David A. Goldfarb
30-Apr-2005, 14:59
Interesting, Ole, but no, it's a classic Tessar-type that dates from 1925-28.

Ole Tjugen
1-May-2005, 04:56
David, if it's a pre-1930's f:3.5 Xenar, it has to be a "Typ D"! The Tessar types of that age were all f:4.5 AFAIK... There's a 1928 150/3.5 Typ D Xenar sitting in my display cabinet waiting for me to repair the shutter.

John Kasaian
1-May-2005, 05:36
Thanks to everyone for your advice---especially Tracy Storer! I just won a 100 year old C.P. Goerz 19" f/11 series IV double anastigmat on eBay for 12x20 work. Hot dog!

David A. Goldfarb
1-May-2005, 07:42
Ole, what's different about the "Typ D" design? I've dated it from Schneider's serial number list, and I've taken it apart, and it looks like a Tessar.

Ole Tjugen
1-May-2005, 08:07
According to the Vademecum, the Type D is a 3-element lens made "for small cameras only". I think my 150mm is 4 element in 3 groups - like a "regular" Xenar, but reversed: Cemented front group, strongly positive, and an air-spaced rear group which is neutral or slightly negative. From the 1930's on there were other f:3.5 Xenars of Tessar type; mine is 1928 and definitely no Tessar.

David A. Goldfarb
1-May-2005, 08:24
Interesting. My 210/3.5 is a normal 4-element 3-group Tessar with the normal orientation. It's a heavy lens, definitely not for small cameras. Maybe the "Typ D" was only in certain focal lengths, or they started making the Tessar-type Xenar earlier than 1930, or maybe I've got a serial number anomaly.

I use it on the 5x7" Press Graflex, and mounted in the normal way it's just a tiny bit short to focus to infinity, but if I countersink the lensboard, I might be able to do it without hitting the mirror. The stock lens on that camera is a B&L 5x8 Tessar, which is probably around 240mm. The 210/3.5 Xenar just fits on a Graflex 4x4" lensboard, so I suspect it was made for a camera like this. As it is, I use the Xenar indoors when I might want the extra speed, and the Tessar outdoors when I might need infinity focus (and then, miracle of miracles, my 12"/6.8 Gold Dot Dagor in-barrel fits the same flange as the Tessar, so I use that one sometimes too. I have a 19" Apo Artar that also fits the flange, but not enough bellows on that camera, alas).