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Rider
31-May-2007, 09:54
What is an Anastigmat Lens notable for? Is it a brand or are there different makers? Does it come in different focal lengths? Are they always fast lenses?

Ole Tjugen
31-May-2007, 09:57
All modern lenses (one exception only that I know of) are anastigmats.

In the beginning "Anastigmat" was a Zeiss trade mark, but that ended quite quickly and just about everything from everybody was called "Anastigmat".

The term encompasses as I said just about everything - every possible focal length and aperture.

Rider
31-May-2007, 10:01
So a Goerz Anastigmat 120 would just be any old 120mm Goerz?

How about the letters "Dopp" that you often see?

Ole Tjugen
31-May-2007, 10:07
A Goerz Anastigmat can be a Dagor, a Celor, a Dogmar, or...

"Dopp." is an abbreviation for Doppel, which means "double". When used in the context Doppel-Anastigmat it means that the lens consists of two more-or-less similar halves, each of which is corrected for astigmatism.

A Goerz Doppel-Anastigmat ser. III is what later became the Dagor. Serie Ib and Ic became Syntor, then Celor.

Dan Fromm
31-May-2007, 11:06
And then there are all those other doppel anastigmats with no other markings. Most, not all, turn out to be pretty pedestrian dialyte types. This includes entirely too many lenses made by Goerz.

Some plain vanilla anastigmats are still worth using. Kodak Anastigmats, for example. Ignoring Kodak's cine lenses, most KAs are tessars or dialytes.

Fast lenses? Some are, others aren't. I use my 4"/2.0 Taylor Hobson Anastigmat; it is a 6/4 double Gauss type, came from an aerial camera, covers 2x3. And I have a 203/7.7 Kodak Anastigmat in the drawer; a 4/4 dialyte that covers 5x7, and a fine lens that I don't use because I have others at around that focal length that are easier to use with my little cameras.

Ole Tjugen
31-May-2007, 11:16
One of my "strange accumulations" is a "Dopp. Anastigmat" - rear cell is a Zeiss Anastigmat Ser. VII, the front cell is a Zeiss Protar Ser. VII. Same lens(halves) with two different names.

The slowest anastigmat lens I know of off the top of my head is the Goerz Hypergon f:22, which is unusual also in that it has only two elements. Of the more "general" anastigmats the Zeiss Protar ser. V f:18 is also pretty slow.

Erich Hoeber
31-May-2007, 11:32
A Goerz Doppel-Anastigmat ser. III is what later became the Dagor. Serie Ib and Ic became Syntor, then Celor.

Ole -

You should really write a book! I've got the Vademecum and Kingslake and many others, but you're the best resource I know of!

Erich

Ole Tjugen
31-May-2007, 11:47
Erich - that last bit was extracted, summarised and condensed from Hartmut Thiele's "Deutsche Photooptik von A-Z" (2007). And corroborated by Hans Schmidt's "Photographisches Hilfsbuch für ernste Arbeit" (1910).

I just happened to have both within reach... :)

Per Madsen
31-May-2007, 12:09
Erich - that last bit was extracted, summarised and condensed from Hartmut Thiele's "Deutsche Photooptik von A-Z" (2007). And corroborated by Hans Schmidt's "Photographisches Hilfsbuch für ernste Arbeit" (1910).

I just happened to have both within reach... :)

Do you have an ISBN number for Thiele's book ?

Glenn Thoreson
31-May-2007, 12:28
To put it simply, the word Anastigmat means the lens is corrected for astigmatism. Nothing more, nothing less. They come in all focal lengths and speeds. There are double (Doppel) and triple anastigmats, like the Voigtlander triple anastimat I got from Ole. Lens vernacular can be quite confusing. I think they stay awake nights dreaming the stuff up. Ole is a very good source of knowledge on the subject.

Ole Tjugen
31-May-2007, 13:11
Do you have an ISBN number for Thiele's book ?

Sorry, but no. It's a "private printing", but it can be bought from www.lindemanns.de.

Jason Greenberg Motamedi
31-May-2007, 14:05
Anastigmat is a rather odd word. It is (more or less) the negative of "astigmatism" and the double negative of "stigma", point in Greek. So, astigmatism is a lack of point, in other words a lack of sharpness. Anastigmat(ism) means a lack of a lack of point, or good sharpness Confusing?

Jim Galli
31-May-2007, 15:06
The word has more meaning in respect to the non anastigmat lenses from 1840 - 1890+ that the anastigmats replaced. There were multitude of designs but most notable are the Petzval type and the Aplanat or rapid rectilinear lenses. Neither could focus a scene on a flat plane. If you were photographing a group, you might have them stand in a semi circle so the lens would see more of them in focus at the same time. That's why Petzvals have that splendid central sharpness that falls into defocus that is still loved in portraiture after 165 years. Rapid Rectilinears were somewhat better but sill suffered. When the different anastigmat designs hit the fan from roughly 1893 - 1903 it was huge. You could have corner to corner sharpness that just wasn't possible before then.

Now of course we're going backwards collecting and valueing old lenses for their distinct "look" that the folks 100 years ago couldn't abandon fast enough.

Uli Mayer
1-Jun-2007, 15:34
Thiele's book can also be bought in USA at
http://www.camerabooks.com/