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Curt
21-Jul-2013, 01:26
First, what's the difference between a gold dot, gold rim, and no gold? Second is coverage and personal experience with them. Who uses them on formats larger than 8x10? Do they vary in coverage from one to the next in the same focal length, 12". Are they a "smart" buy, ie. are there better choices?

IanG
21-Jul-2013, 01:43
Can't comment on the Gold dots etc but I have and use a 12" Gerz Am Opt Dagor made 1939/40 which was later factory coated, it's a very good lens. A lot is down to the condition of the lens , later Gold dot, rim etc versions are all coated so fetch higher prices.

My own lens was sold with a camera and the second owner had never used it saying it had separation and wouldn't be sharp, it was just years of dirt around the edges. Coverage is quite good plenty of room for movements on 10x8 and it's very sharp. I made contact with the original owner who had been a student and later teacher at the Clarence White School of Photography, he'd bought what he considered the best camera and lens available in 1939/40 a 10x8 Agfa Ansco Commercial View with a 12" Dagor.

When I first tried my Dagor I wasn't expecting too much and was pleasantly surprised by the quality of the lens. If you get a good one they are a smart buy.

Ian

Curt
21-Jul-2013, 02:19
Thank you Ian, they have a fine reputation so after having many Artars I thought I'd look into a Dagor. Of course I'd like nothing better than a brand new Cooke convertible. It's the coverage of the Dagor design that interests me most.

Don Dudenbostel
21-Jul-2013, 04:44
Curt ive owned many Dagors over the years and had ones I liked and others I didn't. My first one was a very nice condition 12" series III in an ilex shutter. It was originally uncoated but over the years had developed a natural bloom which was in effect a coating. I used it in studio for catalog work and food photography and was always pleased. I wound up trading it for a Symmar and always regretted the trade. The Dagor was no better than the Symmar but I liked the color better. I mainly used it on 8x10 but found it covered 11x14 stopped down.

I owned a couple of short Dagors including a 120mm. They were good but nothing special.

A couple of years ago I picked up a 14" gold dot Schneider, a 12" late coated on gold and a gold rim 8". The 8" gold rim was very good with enough coverage for 8x10 and some movements when stopped down. It was sharp and no focus shift.

I was quite disappointed with the Schneider. It was the gold dot variety hand didn't have the coverage of the 12" series III. For some reason Schneider restricted the coverage. The images were too contrasty and harsh looking. The version I had was multi coated if I remember correctly.

The late 12" non gold was great on coverage and looked much mike the Series III but had a dramatic focus shift when stopped down. I had to stop down to focus around f
16 and then go to my working aperture. I didn't care for this lens and sd it.

The little 8" was beautiful in every way. It was a gold rim version. It was sharp, pleasant contrast and had excellent coverage. There was no focus shift and it covered 8x10 with a little movement when stopped down.

I recently purchased a beautiful brass Double Anastigmat 180mm in a very early brass shutter. The glass is perfect but the shutter needs work. Its no problem since I bought it for wet plate. It is a fine lens and typical of even the later Dagors. Dagors are a little soft wide open typically and this is what I was looking for. It's a lovely lens on wet plate.

All Dagors with the exception of the Schneider have common characteristics. Now having owned a very early Double Anastigmat (Dagor) and several others produced over a century all have a common look. It's amazing until Schneider they really had not changed other than coating.

My overall opinion of Dagors, they're good lenses if you get a good one but there are dogs out there. There good on coverage except the Schneider versions.

Overall they are no better than a Symmar or other quality plasmat. Matter of fact Dagors generally aren't as sharp as a modern plasmat like the Symmar or sironar, Fuji or Nikkors.

The buzz about them has driven the price to redicilous heights. The same thing has happened to the 12" & 14" commercial ektars. While good they're no better or not as good as modern lenses. IMO a good clean gold rim Dagor is worth no more than a comparable Symmar, Nikkor, Fuji or Rodenstock. This is just my opinion and experience. I would never personally pay more than $400 for a clean non gold late coated Dagor if it works properly.

There was a gentleman who used to post here but I understand he passed away. He was with Burke and James at the time Goerz changed to the gold rim and then gold dot. He stated and I've read this in a magazine article thirty years ago that there was absolutely no difference other than cosmetics. The gold rim was simply a marketing gimmick. If I remember correctly the gold dot came when goerz ran out of gold rims and had to come up with something to fill an order. They took a black retaining ring and put a gold dot on it and said it was a newer version and improved. Marketing!

goamules
21-Jul-2013, 05:39
I like all Dagors, and have about 5. With less air spaces, they more contrasty than most other lens types, even uncoated. As far as the Golden Dagor, I don't know, but the Gold Dot was supposedly applied to lenses that were centered with a special new device according to a lot I've read. I think the "it was just marketing" story is just being repeated after one person said it in View Camera, but that statement may be from a person that didn't know. There are others who worked with or at Goerz that say the Gold Dots were specially made:
https://groups.google.com/forum/#!topic/rec.photo.equipment.large-format/40y9sx74q28

Curt
21-Jul-2013, 06:00
Thank you Don, that's a lot of very good information! I'll re-read it again to be sure. I heard the same about the Red Dot on Artars being a marketing tool. When it comes to lenses I've found it a little like buying a used car. You never know what it'll do until you test it out. I have an 8 1/2" and a 14" Kodak Commercial Ektar lens. They have lived up to their reputation. I got luck maybe. The 210 and 300 Symmars I have are fine too as are the 305 and 360 Apo Nikkors. It gets more interesting looking at ULF lenses though. The dollar signs pop up quickly on some. I go get a little tired of reading "mint" and "rare" but that's the program.

It's the coverage that's the draw for me on the Dagor lenses but I'm still looking at all of what's available. 11x14 coverage and up.

Leigh
21-Jul-2013, 06:20
To answer the original question...
The angle of view of the Dagor is 90° when stopped down.
Given a half-angle of 45°, the distance from lens axis to the IC perimeter equals the focal length.
So for a 12" lens, the IC would have a radius of 12".

=====

Dagors were made for a long time in various locations.

I have an 8¼" Gold Dot that was made in Switzerland.
The dot is definitely not an after-thought, since the arrangement of the lettering left an obvious space for the dot.

99111

It is my understanding that the gold rim was a marketing ploy used when the Gold Dot lenses were not available.

Lynn Jones, former VP at B&J, made the following comment regarding "gold rim" Dagors in an earlier thread:
"Regional sales manager needed 6 Dagors but the bezels had not been plated (black) so Harry said send them anyway."
[Note that the bezels were brass, and thus appeared "gold" before painting.]

- Leigh

Refs:
Full post here: http://www.largeformatphotography.info/forum/showthread.php?87082-Goerz-Berlin-never-made-quot-gold-quot-lenses-did-they&p=847576&viewfull=1#post847576
Full thread here: http://www.largeformatphotography.info/forum/showthread.php?87082-Goerz-Berlin-never-made-quot-gold-quot-lenses-did-they

Dan Fromm
21-Jul-2013, 06:30
Curt, opinions about Dagors' coverage vary a lot. For an illustration and a good laugh, see http://www.largeformatphotography.info/forum/showthread.php?13109-Lousy-Dagor

My friend Eric Beltrando wrote a ray tracing program and collected a small heap of lens' prescriptions from patents and, for Boyer lenses, for as much of the Boyer archives as he has. The results, with coverage estimates three stops down from wide open are on www.dioptrique.info.

He did the exercise for a number of different Goerz Dagor prescriptions, also for several vintages of Boyer Beryl prescriptions. The Beryl is a Dagor clone. Boyer claimed that Beryls cover 85 degrees. This matches Goerz' claims for f/6.8 and f/7.7 Dagors. As Eric calculated 'em, and using his coverage criterion, they all cover no more than 70 degrees. He's advised me to expect no more than 55 degrees from a Beryl "in stringent applications."

Berthiot made a number of Dagor clones. Their coverage claims for the f/6.8 Perigraphe shrank from 95 degrees in 1912 (see http://trichromie.free.fr/trichromie/index.php?post/2011/01/27/PERIGRAPHE) to 85 degrees in the mid-1930s (see http://www.collection-appareils.fr/accesnotices/html/lire_repertoire?repert=som_berthiot&marque=Som%20berthiot&modele=Catalogue&PHPSESSID=333965b3c0b5e4652c9d3802b532215d) to 65 degrees in 1950 (a SOM Berthiot brochure that I have). Coverage is a sometime thing.

goamules
21-Jul-2013, 07:21
If anything, people buy the Golden and/or Gold dot Dagors because they were made during the period after Goerz started using the precision assembly alignment tool. Which helped ensure the highest quality. I have a Golden, and it's fantastic. I have a few 1920s ones too. Which do you think had more precise manufacturing?

David attributed this in another post:
"The best Dagors were made after 1963 [the "gold" period] when Goerz perfected a device to centralize the elements within two seconds of arc. This is equivalent to five feet in 100 miles. How do I know this? I built the device and also filled in as a lens fitter from time to time."
March 1986 issue of "Shutterbug" had a letter from Edward Bolsetzian who worked at C.P. Goerz (http://www.largeformatphotography.info/forum/showthread.php?87082-Goerz-Berlin-never-made-quot-gold-quot-lenses-did-they&p=847522&viewfull=1#post847522)

Don Dudenbostel
21-Jul-2013, 08:21
Lynn Jones is the person I was trying to remember. I would take his word since he was so closely involved in the industry.

Like I mentioned I shot many catalogs and ads with Goerz lenses including three RD Artars, 14, 16 1/2 and 19. I never owned a non red dot but my understanding is the only real difference is the RD is coated and the other is not.

I also failed to remember I owned a pristine 14" Dagor 7.7 that I had mounted in a shutter. I used this along with the 12" and RD Artars all through the 70's and into the 80's for many national ads an catalogs. No client ever questioned the quality of the images or what lenses I shot with. When I went to more modern glass, symmars and g Clarons no one ever knew. there's just not that much difference. At least it wasn't visible in 8x10 and 11x14 ektachrome.

I've always felt there was a little more coverage from the Dagors vs modern plasmats with the exception of the Sironar S and first generation Fujinons with the engraving on the inside of the retaining ring.

If you're looking for a reasonable and more modern lens with exceptional coverage and at a very cheap price take a look at the Fujinon 1st generation like the 250 f6.7. Huge coverage and very sharp. I owned one and sold it but wish I had kept it. I still have a 125 and 150. The 125 covers 5x7 stopped down and the 150 covers with good movement. They are exceptional bargains.

Bernice Loui
21-Jul-2013, 09:38
It really depends on what you're after in the image...

Yes, the Dagor can "cover" out to say 80 degrees and be some what reasonable in shaprness-en-all-that. What is often not discussed about lens coverage is light fall off which applies to any optic.. and the greater the angle of coverage, the greater the light fall off. Makes zero difference if this is a Dagor or Symmar XL, Grandagon or ...

To get uniform illumination some means of correction must be applied, example being a center filter that matches the optic's innate light fall off.

Do not own a Dagor or most any lens unless you have had the chance to test it and verify it is not a dud, but know what to expect. In the case of Dagor, they typically have varying amounts of focus shift. Do check this before writing off the lens as a dud.

There are other factors beyond sharp, contrast and modern shutters, there are other factors such as out of focus rendition, contrast range and color rendition. What Dagor fans appear to like about this specific optic has more to do with out of focus rendition, contrast range (many already here know I'm not much a fan of modern Plasmants due to their exaggerated high contrast and appearance of sharpness) and ability to cover for it's given physical size.

What apertures will be used.. Everything in the image to be sharp or selective focus or... this is another very significant lens choice factor.

The 12" Dagor was common on 8x10 film cameras..

Consider all the other factors, try a bunch of lenses to see what works for you then decide.. Don't base lens choices on coverage or reputation alone. This is more a question of what optic meets your image making needs, not what others have to say as each of these image making tools must server your needs and your methods of working..



Bernice






First, what's the difference between a gold dot, gold rim, and no gold? Second is coverage and personal experience with them. Who uses them on formats larger than 8x10? Do they vary in coverage from one to the next in the same focal length, 12". Are they a "smart" buy, ie. are there better choices?

Jim Noel
21-Jul-2013, 11:49
I own and use five Dagors, but no Schneiders. I do have an early 12"double anastigmat, plus the four labeled "Dagor" . I have never had a bad one. I use a 12" as the basic lens on my 7x17". At f-22 it covers very well.
Jim

Dan Fromm
21-Jul-2013, 13:30
Jim, do you enlarge your 7 x 17s or contact print them?

William Whitaker
21-Jul-2013, 16:49
I have a 12" Dagor in a barrel; makes a great paperweight. Does the job well at all f/stops.

Don Dudenbostel
21-Jul-2013, 19:33
I have a 12" Dagor in a barrel; makes a great paperweight. Does the job well at all f/stops.


Very funny Will.

I can't say any were paper weights but my late version 12" was disappointing as was the Schneider 14". I'd much rather had my old series III and 14" f7.7.

Don't get me wrong because I do like them but they're not as special as prices would suggest.

William Whitaker
21-Jul-2013, 19:50
I'm not saying my lens is bad, but it does hold papers down pretty well. I used it for a time on 11x14 and found the corners unacceptably soft. For 8x10 it's a good lens.

Curt
22-Jul-2013, 03:05
I want to thank all of you for the rather intense and in depth class on Dagor lenses. Anyone who reads this thread will get the key points when looking for, evaluating, and choosing a lens. I know I'm going to be more educated in any purchase.

Jim Noel
22-Jul-2013, 06:39
Contact. I have never heard of an enlarger that would take a negative this size, and no way am I going to waste time with digital.

Dan Fromm
22-Jul-2013, 08:28
Contact. I have never heard of an enlarger that would take a negative this size, and no way am I going to waste time with digital.

Jim, thanks for the reply. One idea that tends to get lost in discussions of coverage is how much the neg will be enlarged. Contacts demand lower image quality in the corners than do negs that are going to be enlarged.

Cheers,

Dan

Jim Noel
22-Jul-2013, 08:32
Jim, thanks for the reply. One idea that tends to get lost in discussions of coverage is how much the neg will be enlarged. Contacts demand lower image quality in the corners than do negs that are going to be enlarged.

Cheers,

Dan

That's your opinion. After more than 70 years of LF and ULF photography, I have to disagree. A discriminating photographer, or collector will look as closely at the corners as at the center of the image.

Dan Fromm
22-Jul-2013, 09:12
That's your opinion. After more than 70 years of LF and ULF photography, I have to disagree. A discriminating photographer, or collector will look as closely at the corners as at the center of the image.

I agree completely. But the corners in a negative that's going to be contacted don't have to be as good as those in a neg that's going to be enlarged to get the same image quality in the final print's corners.

cosmicexplosion
22-Jul-2013, 12:44
solid argument!



David attributed this in another post:
"The best Dagors were made after 1963 [the "gold" period] when Goerz perfected a device to centralize the elements within two seconds of arc. This is equivalent to five feet in 100 miles. How do I know this? I built the device and also filled in as a lens fitter from time to time."
March 1986 issue of "Shutterbug" had a letter from Edward Bolsetzian who worked at C.P. Goerz (http://www.largeformatphotography.info/forum/showthread.php?87082-Goerz-Berlin-never-made-quot-gold-quot-lenses-did-they&p=847522&viewfull=1#post847522)[/QUOTE]

E. von Hoegh
22-Jul-2013, 13:42
The Dagor is a 65~70 degree lens, according to my experience ( 6", 8 1/4", 9 1/2", 240mm, 30cm, and 14") and some old references I have. You might do 85 degrees for contact prints.
Dan's mention of 55 degrees for critical work is interesting, this is just about what Schneider gave as the coverage (53?) for the 14" MC gold dot version.

Don Dudenbostel
22-Jul-2013, 20:03
The 14" Schneider gold dot that I owned had a very limited image circle. It covered about the same as the 14 red dot artar I use to own. The Schneider was totally different than the 14" f7.7 that I used to own. The f7.7 covered 11x14 with movements.

William Whitaker
26-Jul-2013, 10:48
I have a 12" Dagor in a barrel; makes a great paperweight. Does the job well at all f/stops.

I want to say that I do not in any way mean to disparage Dagors. They are great lenses. The incident referred to above actually happened earlier this summer as I had a couple of fans going in the living room to try to stay cool and some papers wanted to take flight. The nearest thing in reach to use to hold them down happened to be my 12" Dagor. It was funny at the time to use a fine old lens for such a mundane task.

I have a set of three Dagors marked C.P. Goerz Am. Opt. Co. (7", 8 1/4" and 9 1/2") that I really like and which form the basis of my lens kit for 5x7 and include the long side of the format, the diagonal and twice the short side of the format, which is a pleasing trinity of focal lengths to my eye for most conventional (non-panoramic) formats. The last two cover 8x10 as well, making them even more useful. I especially like the 9 1/2".

Steve Hamley
30-Jul-2013, 06:46
Folks,

I have a slew of them, from Series III (and IV) Double Anastigmat to Gold Rim and Gold Dot. What everyone has said is fairly correct given sample variation over the years. If you're enlarging and want the sharpest corners, 75 degrees is a reasonable number. Contact printing 85 degrees. Earlier ones had more coverage or at least more illumination. Later ones were technically better. I have some that shift focus and some that are more like modern lenses (less focus shift). My 10-3/4" seems to shift the most, and I always try to focus at at least f/11 with this lens. My 12" Gold Dot shifts little or none.

It's always good advice to focus as close to the taking aperture as possible with any lens, modern or classic.

They're fine lenses but some aren't as good as others. Trying is the only way to tell.

As far as coverage above 8x10, depends on the specific lens and model. I have a 19" Series IV Double Anastigmat that will cover 20x24 wide open according to the person (very reputable and does have a 20x24) I bought it from. f/7.7 Double Anastigmats and Series III 14" and above should cover any reasonable format.

BTW, I also had a 14" Trigor and a single-coated 14" Schneider Kern. They were both extremely flare prone, the Kern being unusable pointed into the light. Neither had the coverage of other Dagors so I "uploaded" them. The Kerns and Trigors are cult lenses, you can do much better with the other series.

Cheers, Steve