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Thierry Schreiner
17-May-2008, 17:24
Hi to all,

2 questions, please:

What dimension is the filter thread on the G-Claron 355mm Dagor type are?

Can someone with user experience comment on this lens?


Thank you in advance for you help & best regards

Thierry Schreiner

Dave_B
17-May-2008, 18:05
Hi to all,

2 questions, please:

What dimension is the filter thread on the G-Claron 355mm Dagor type are?

Can someone with user experience comment on this lens?


Thank you in advance for you help & best regards

Thierry Schreiner

Thierry:
Use the search feature on this forum. You will find people love this lens as do I. The filter thread is 77mm.
Cheers,
Dave B.

Thierry Schreiner
17-May-2008, 18:18
Dave,

Thank's a lot for your reply, but the first type of the G-Claron was of Dagor design with 6 lenses in 2 groups, and I guess it has a smaller thread than the late 355 G-Claron, which I actually have and is one of the best lenses I have used.

Attached are the Schneider Kreuznach archives.

The 355mm G-Claron is listed as being in preparation, but the filter thread is not mentioned.

http://www.schneiderkreuznach.com/archiv/pdf/g_claron.pdf


Best regards

Thierry

neil poulsen
17-May-2008, 21:25
I don't have one, nor have I used one. But, I've read quite a bit about this lens, and I'm inteested in getting one myself. (Someday.)

It's a plasmet design, which is pretty standard modern among large format lenses of this focal length.

It's capable of quite a large image circle for this focal length. There was something about the manufacture of the G-Clarons that gave them this advantage. The data published at the Schneider website will somewhat underestimage the image circle that's capable of this lens.

It's single-coated. (Sometimes you'll see references that it was multi-coated, for example, older Calumet catalogs. But, that's not the case. It was intended for interior use, and multi-coating was deemed unnecessary.)

It's was designed for closer work, versus infinity. But stopped down, it performs quite well at infinity.

People like this lens for 8x10, because of it's small size, and because of its rather large image circle.

Thierry Schreiner
18-May-2008, 01:48
Neil,

Thank's a lot for the info.

But my question refers to the Dagor design G-Claron, not the Plasmat design, which was developed later.

I have a late 355mm G-Claron, which performs great, .... never ending image circle, .... outstanding sharpness, almost all you can ask from a lens. The only lens I will definitely never trade in. But huge, and a pity it doesn't have a larger aperture.

So my 2 questions:

What is the filter dimension of the Dagor type 350mm G-Claron?

Does the image quality from the Dagor design lens differ from the later Plasmat design, and is there any noticeable difference in image quality?


Thank you and best regards

Thierry

neil poulsen
18-May-2008, 06:29
Oops. I missed that. Don't know nothin' 'bout that.

Ernest Purdum
18-May-2008, 07:33
The filter thread is M 67 by 0.75 thread pitch. This is one of the easier ways to distinguish between the two types.

Thierry Schreiner
18-May-2008, 09:36
Ernest,

Thank's a lot for the info. This helps.

Best regards from France

Thierry

Really Big Cameras
18-May-2008, 10:24
Theirry,

According to Jim Galli, there was no Dagor-type G Claron in the 355mm focal length. In this post (http://www.apug.org/forums/forum44/29141-some-dagor-s-non-dagor-dagor-s-i-have-loved-rlp-really-long-post-2.html#post324367) on APUG, Jim states that the older 355mm G Claron with the 67mm filter threads is a plasmat with slightly less coverage than the newer version with the 77mm filter threads.

Kerry Thalmann
Really Big Cameras

Dan Fromm
18-May-2008, 11:00
Kerry, I'm afraid that like you and me Jim is sometimes mistaken. Look at this http://www.schneiderkreuznach.com/archiv/pdf/g_claron.pdf.

Write "I will not use secondary sources when the primary source is at hand" one hundred times.

sanking
18-May-2008, 11:08
Neil,


Does the image quality from the Dagor design lens differ from the later Plasmat design, and is thee any noticeable difference in image quality?


Thank you and best regards

Thierry

As Kerry notes below, as per Jim Gali there is no Dagor design alterntive in the 355 G-Claron.

Dagor design is definitely different from plasmat design. In Dagor design you have two groups with three cemented elements, and total of four air-to-glass surfaces. Plasmst design is similar to Dagor, but in both groups one of the elements is separated by air, giving you six air-to-class surfaces.

With single coated lenses Dagor design gives slightly more contrast than plasmat design, but plasmat should give more resolution at larger apertures. Dagor designs usually also give slightly more coverage than plasmat designs, but not always. The Computar design is plasmat and gives coverage much greater than normal Dagor design and about on a par with wide-angle dagors.

Sandy King

Really Big Cameras
18-May-2008, 11:55
Kerry, I'm afraid that like you and me Jim is sometimes mistaken. Look at this http://www.schneiderkreuznach.com/archiv/pdf/g_claron.pdf.

Write "I will not use secondary sources when the primary source is at hand" one hundred times.

Dan,

It's been 30 years since I took high school German, but I don't see anything in that document that says there was ever a 6/2 Dagor-type G Claron in the 355mm focal length.

In fact, the only mention of the 355mm focal length is the table that lists it as "vorbereitung". Which translates to "in preparation" or "in development".

Am I missing something?

Kerry Thalmann
Really Big Cameras

Really Big Cameras
18-May-2008, 12:22
I also happen to have one of the older style 355mm G Clarons. The 67mm filter thread size, direct fit in a Compound No. 4 shutter and serial number 12,439,xxx all confirm that is it the older style G Claron. I counted the reflections when I got it and was disappointed to learn it wasn't a Dagor type lens. I just went back and double checked, and it is without a doubt a plasmat (6/4) construction, just like my newer 355mm G Claron (Copal No. 3 shutter, 77mm filter threads, 14,577,xxx serial number).

Kerry Thalmann
Really Big Cameras

Dan Fromm
18-May-2008, 12:56
Kerry, I noticed that too. But given how sketchy Schneider's archives are, that one pamphlet is evidence that they intended to make 355 mm dagor type G-Clarons. Whether they actually did is still an open question to which the answer might be at hand.

Thierry, will you please count reflections in your 355 G-Claron and tell us what it is?

Cheers,

Dan

Really Big Cameras
18-May-2008, 13:05
Kerry, I noticed that too. But given how sketchy Schneider's archives are, that one pamphlet is evidence that they intended to make 355 mm dagor type G-Clarons. Whether they actually did is still an open question to which the answer might be at hand.

To me, that one pamphlet simply tells me they had plans to develop a 355mm G Claron. It doesn't tell me anything about the construction.

Perhaps during that development they determined that a 6/4 plasmat would be both cheaper to build and give better performance. That might also be why the ended up re-designing the entire G Claron line and switching from 6/2 Dagor type to 6/4 plasmats in all focal lengths.

I don't claim to have every brochure Schneider published, and I certainly haven't seen more than a couple of the older style 355mm G Clarons, but I haven't seen any evidence (first hand, or otherwise) that Schneider ever made a 6/2 Dagor type G Claron in the 355mm focal length. Have you?

Kerry Thalmann
Really Big Cameras

Dan Fromm
18-May-2008, 15:25
Kerry, beyond that brochure, no.

If Thierry has the lens he can check for us. If he's contemplating looking for one, there's no help to be got from him.

Proving non-existence is hard. In the spirit of using primary sources, I've just sent Schneider an e-mail asking whether any 355/9 G-Clarons made to the design in the 1976 brochure were sold. Who knows, they may respond.

I can't read minds, don't know why Schneider replaced dagor type Symmars with a 6/4 plasmat type that, according to the VM, was little better. The 1964 Symmar brochure shows a plasmat cross section; the VM says the change (f/6.8 dagor type to f/5.6 plasmat type) occurred in the early '50s. I'm a little surprised that early f/9 G-Clarons weren't just process Symmars, as the later ones seem to be.

Cheers,

Dan

Really Big Cameras
18-May-2008, 20:54
Proving non-existence is hard.

This is true. Proving existence is much easier. It only requires one example.


In the spirit of using primary sources, I've just sent Schneider an e-mail asking whether any 355/9 G-Clarons made to the design in the 1976 brochure were sold.

Did you specifically ask them if they ever made any 355mm G Clarons of 6/2 construction?

Why do you think the brochure you posted the link to was from 1976? The date code on the final page seems to indicate a printing date of 1968. Based on the serial number, my older style G Claron (67mm filter size) would have been produced ~1973. So, listing the 355mm G Claron as "vorbereitung" in a brochure from 1976 would not make any sense as they would have been in production for at least 3 years by then.

Kerry Thalmann
Really Big Cameras

Kirk Fry
18-May-2008, 21:16
Not to be too picky here but the word Vorbereitung right after the data for the 355 mm lens in the data chart means "in preparation" in German according to the translation sites.
So I would say that the jury is still out. Maybe they never sold one?

K

Dan Fromm
19-May-2008, 04:41
Kerry,

I've forwarded the e-mail I sent to Schneider to you at sales@reallybigcameras.com .

Why do I think the brochure is from 1976? Because that's what Schneider's site says. The text that precedes this http://www.schneiderkreuznach.com/archiv/pdf/g_claron.pdf
link reads "G-Claron, Objektive für Büro-Kopiergräte (9/76)" It could well contain a typo.

Cheers,

Dan

Really Big Cameras
19-May-2008, 08:47
I've forwarded the e-mail I sent to Schneider to you at sales@reallybigcameras.com .

Thanks, but you didn't ask them specifically if any 355mm G Clarons of 6/2 construction were ever produced. Since there is no specific information about the construction of the 355mm G Claron listed in that brochure, asking them if they produced any based on the design listed in that brochure could still lead to an ambiguous answer.


Because that's what Schneider's site says. The text that precedes this http://www.schneiderkreuznach.com/archiv/pdf/g_claron.pdf
link reads "G-Claron, Objektive für Büro-Kopiergräte (9/76)" It could well contain a typo.

It's either a typo or a cut-n-paste error from the entry directly above. The date code on the final page of the brochure clearly says "VI 68" which means June, 1968 based on the date code format Schneider used on all their brochures up until sometime in the mid-1970s. If you check other Schneider brochures from that time period (the C Claron one from 6/68, the Repro Claron from 2/72, the Symmar-S from 8/72, etc.) you'll see all the dates listed match this date code format as printed on the final page of the brochures.

And, as I said previously, it wouldn't make any sense for a brochure from 1976 to list the 355mm G Claron as "in preparation" when I have an example that was produced in 1973.

Kerry Thalmann
Really Big Cameras

Thierry Schreiner
24-May-2008, 16:20
Dear all,

First of all sorry for my late response, and thank's a lot for your input.

I doublechecked my lens, and it is a plasmat type of the first generation with a 67mm filter size.

So, definitely no one seems to have seen a 355mm Dagor type G-Claron so far, if such a beast exists.

Let's keep on looking.


Best regards from France

Thierry

Dan Fromm
24-May-2008, 16:42
Thierry, I've asked Schneider, fear they think they've answered my questions. The one concrete answer I got was that serial numbers before 11,000,000 should be dagor type, after should be plasmat type. They haven't responded to a very direct question about 355/9 G-Clarons with s/n < 11,000,000.

So what s/n is yours?

I've had three 240/9 dagor type G-Clarons, 10 435 819, 10 819 851, and 10 943 653.

Cheers,

Dan

Thierry Schreiner
25-May-2008, 13:40
Hi Dan,

Here is where it really gets complicated with the serial numbers.

According to some, the G-Clarons with serial numbers between 10 and 11 000 000, are supposed to be Dagor type lenses.

I have the following Dagor G-Clarons:

210mm S/N 11 531 531 (nice number)
240mm S/N 10 119 920
240mm S/N 12 175 606

The 355mm G-Claron I was referring to previously has S/N 11 401 024. Should be a Dagor type, but is definitely not.


The G-Claron I use mostly is the "Jim Galli" Dagor type, the 225mm f9,5, made up of a 240mm front element and a 210mm back element.

This combination is really great, optically outstanding with a never ending image circle.

Thank's a lot to Jim for sharing his experience.


Best regards

Thierry

Dan Fromm
25-May-2008, 14:02
Thierry, Marie-Odile Helfrich, dont l'addresse est @schneiderkreuznach.com, m'a ecrit "The first design has been bought until Serie no. 11.000.000 and after this Serie number the second design has been sold too." Un peu ambigu, non?

Je crois q'elle voulait dire que les G-Clarons avec numero de serie moins que 11,000,000 sont du type Dagor et que les G-Clarons avec numero de serie plus que 11,000,000 sont du type Plasmat. 11, 401, 024 me semble plus grand que 11,000,000.

La demoiselle n'est pas "some;" je crois q'elle est la voix de Schneider.

And what are your two 240s?

Amicalement,

Dan

Thierry Schreiner
25-May-2008, 14:08
Dan,

Bonsoir,

The 3 lenses I listed are definitely all Dagor type G-Clarons.

G-Claron 210mm S/N 11 531 531
G-Claron 240mm S/N 10 119 920
G-Claron 240mm S/N 12 175 606

Hence my doubts about the S/N.


Bien le bonjour de France.

Thierry

Dan Fromm
25-May-2008, 15:26
Oh my. So much for Schneider's mouthpiece.

Thank you very much.

Jon Wilson
26-May-2008, 19:01
I may have missed the reference in going through this thread, but I have a 355mm G-Claron which fits a Compound #4 shutter (actually these cells will switch with my
210mm Schneider lens and has proper cell spacing), my 355mm G-Claron is a serial # above 11 million, but has a 55mm filter. I don't have this lens in front of me and even if I did I am not certain of the proper way to count the reflections to determine if it is a dagor type or a plasmat type lens.

Jon

Dan Fromm
26-May-2008, 20:02
Jon, if it is a plasmat type each cell will show four strong reflections and one weak one; if a dagor type, two strong reflections and one weak one. The strong reflections come from glass-air interfaces and are easy to see, the weak reflection comes from a glass-cement-glass interface and can be very hard to see.

Ole Tjugen
27-May-2008, 01:14
Dan, you have one more typo: The Dagors have two strong and two weak reflections.

And Jon, that's a #3 Compound. Hang on while I check the reflections on mine. :)

Ole Tjugen
27-May-2008, 02:32
My 355 G-Claron is in a Compund #3 shutter (shared with a 210mm f:4. Xenar), has serial number 11 756 xxx, and is definitely a Plasmat.

Dan Fromm
27-May-2008, 02:49
Dan, you have one more typo: The Dagors have two strong and two weak reflections.

And Jon, that's a #3 Compound. Hang on while I check the reflections on mine. :)Thanks for the correction, Ole. I've been making stupid mistakes all weekend. This is just another bad sign.

Jon Wilson
1-Jun-2008, 19:23
Thanks for the help Dan and Ole. My 355mm G-claron which shares the 210mm xenar cells and a compound #3 shutter. It has 4 strong reflections, i.e., 2 large and 2 smaller ones, but all strong reflections, and thus must be the plasmat. The 355mm's sn11708xxx.

Jon

Dan Fromm
2-Jun-2008, 03:06
Jon, thanks for waking me up. I've had further news from Schneider and have decided that I may have misunderstood the first useful response I got.

First useful response was "The first design has been bought until Serie no. 11.000.000 and after this Serie number the second design has been sold too."

I then asked "Is it possible to know whether there are any 355/9 G-Clarons with serial number less than 11.000.000?" and was told "yes some had been sold with serial number less than 11.000 000"

Cheers,

Dan

Ole Tjugen
2-Jun-2008, 03:41
My experience with Schneider is that they are extremely good at answering the exact question you asked. So short questions must be extremely precisely formulated to get an answer to the question you thought you were asking! :)

Jan Pedersen
2-Jun-2008, 06:50
Sounds like there could be a difference in how the changes were made between various focal lenghts. I have a 240 Dagor type with serial # 11,9xx

Dan Fromm
2-Jun-2008, 07:26
Yep. If you'll read the entire thread, you'll find reports of other dagor types with serial numbers > 11,000,000.