Lens Identification

[MichaelPRyan]

I purchased a Gundlach 5/7 Field Camera and it came with this lens. Reads - Doppel Anastigmat Heligonal 1:5.7 f=24cm and on the bottom, G Rodenstock Munchen. Could someone identify it? It has some separation on the edges but the glass isn't horrible given its obvious age. Is it an early Dagor? I've looked and looked online and can't find anything on this particular lens esp the 5.7. Is this worth keeping? I don't mind the look of older lenses but I know nothing of the merits (if any) of this lens. Thanks in advance.

[Dan Fromm]

You did't look. Try this google search: https://www.google.com/search?as_q=r...pe=&as_rights=

[Jim Noel]

Is this worth keeping? If you don't think so I will be happy to take it off your hands.

[Jim Andrada]

DAGor= Doppel Anastigmat GORtz (I know - there should be an Umlaut over the O to really make it the same as Goertz but I don't think they worried about that small detail.)

As to the differences between the Rodenstock Doppel Anastigmats and the Goertz/Görtz Doppel Anastigmat I know not. But Dan does! And if you're nice enough to him he might even tell you tell you.

[MichaelPRyan]

You did't look. Try this google search: https://www.google.com/search?as_q=r...pe=&as_rights=

I did look. I wouldn't lie to you.

[Dan Fromm]

Fine. You looked. You didn't look well.

All teasing aside, click the link I gave you and read the pages it returns.

Jim, if you do the same you'll find that the Heligonal is not a Dagor clone. Dagors are symmetrical. That is, a Dagor is a pair of cemented triplets. The Heligonal's front group is a cemented doublet, its rear group is a cemented quadruplet, if that's the right use of the word. I didn't know until I looked it up. Old Rodenstock lenses are out of my normal range.

I just looked it up in Fabre (1906 supplement). He likes it, says that it is separable.

[EdWorkman]

Jim
The 'e' after a vowel is the way to write an umlaut if an umlaut is not available.
And for other folks, it makes the vowel sound very different.
I went to school with Shrow-ders with oe, but later [much later] there was a popular song and still later an NFL QB name wherein propernunciation was at least attempted.
Those came out Donka Shayne and Shray-der, but ..... Then there was an NFL player who got a real umlaut on the back of his jersey
regards
Ed

[Dan Fromm]

It isn’t Goertz. It isn’t Görtz. It isn’t Görtz. It isn’t Görz. It is Goerz in all the catalogs and in the Dagor patent.

[MichaelPRyan]

When separated it falls somewhere in the ballpark of 400mm. Thereabouts. Would I need a separate scale for the f stops then? It showed two scales on the original brass barrel.

[Dan Fromm]

Yes.