Goerz Dagors...What's so special?

[Scott Peters]

The look. And my 12 inch covers 7x17...really.

 

[sanking]

The look. And my 12 inch covers 7x17...really.

I am thinking that you bought a 12" Dagor from me some years ago? If this is the one, that lens actually covers 12X20", which is unusual for a 12" Dagor. In fact, even some 14" Dagors do not cover. Of course, it was pretty soft on the corners, even stopped down, but the circle of illumination was there.

Sandy King

 

[Scott Peters]

I am thinking that you bought a 12" Dagor from me some years ago? If this is the one, that lens actually covers 12X20", which is unusual for a 12" Dagor. In fact, even some 14" Dagors do not cover. Of course, it was pretty soft on the corners, even stopped down, but the circle of illumination was there.

Sandy King

Yes it is. Still enjoying it with my 7x17. Corners seem quite nice on the 7x17 stopped down. Thank you Sandy.

 

[renes]

Angulon 165/6.8 or Goerz Dagor 165/6.8?

Angulons are supposed to be a Dagor-type lenses.
How they differ in image character and quality?
Do you see any differences?

 

[Bruce A Cahn]

The main advantage of a Dagor is that it has low contrast while being very sharp. This quality makes it very desirable for landscape photography , where there is often a problem with too great a contrast range in the subject. Also they have a lot of coverage, as mentioned above. I had several which I used as everyday lenses. The problem with them is that the shutters are old and most of them are inaccurate. I did have one mounted in a new shutter, and it was a great performer, but eventually I replaced all my vintage glass with current lenses.

 

[Kevin Frost]

Notes on Dagors. I agree that the Dagor is a valueable lens for lots of reasons. But a fussy lens to use. I've never been able to focus mine (165, 101/4", 300) with open aperture. Generally I have to stop down to near f11before things become crisp enough to focus. But another thing that deserves mentioning is that many Dagor's suffer from focus shift. You might not notice it because it's slight but it happens with some, though not all. I believe that Adams recommended focusing the Dagor at or near the taking aperture, which can be hard to do in low light situations. But for those who have experienced dissapointment with the Dagor regarding sharpness this ought to be checked. An easy way to do it (maybe this is well known?) is to set your camera up as an optical bench by removing the ground glass but using a loupe so you get an ariel image. In effect your camera becomes a telescope. I made a panel to replace the camera back with a hole drilled through the middle and loupe attached. Very simple. But this will show you directly what your glass is doing for you. Generally all lenses are brilliant right in the center. What makes a good one is how well it preforms at the edges. By swinging the front and racking out to get it in focus you can see it clearly. Usually what happens at the edges is color fringing. When I got my prized Gold Ring Dagor I was delighted to discover that there was no focus shift at all, and more, the lens appeared to be apochromatically corrected right out to the edge of the field, which was a massive 85 degrees. No color fringing. BTW, 85 degrees is what an Angulon will give you so the 165 Dagor will cover 8x10, a valuable lens.

 

[Rick A]

I have a 10 3/4" that came off of an 18x24" process camera. I'd be willing to swap for a Mamiya C-330. Its that or I build a LF camera to use it with.

Rick

 

[Ole]

Angulons are supposed to be a Dagor-type lenses.
How they differ in image character and quality?
Do you see any differences?

Angulons are reverse Dagors, and even if they were "normal" there is no reason why they would be similar to other Dagor-type lenses - as indeed the Dagor-type lenses are different.

Angulond are optimised for larger coverage with less mechanical vignetting, thus less light fall-off. Dagors are better optimised for central sharpness.

 

[Mike1234]

DAGOR users please don't be offended but I've never understood the advantage of using a lens with "less contrast" unless one is shooting transparencies. It seems to me the best results are attained with careful exposure and development. I would worry that the shadow detail (shadow contrast) would suffer from what is essentially fogging the film during exposure.

Again, I intend no offense and I've seen zillions of gorgeous images shot with them many of them by you guys here on APUG. I'm just confused about the advantage of fogging the shadows rather than exposing more and developing less. But, I've never used one so I'm really only speculating.

 

[David A. Goldfarb]

I think Dagors actually have pretty good contrast, particularly if they're clean and coated. Even uncoated Dagors have reasonable contrast, as long as they are clean, and it's pretty common for older lenses to have some haze that is often cleanable. In their day this was one of their main attractions, because inherently faster or sharper designs, like the Planar, had too many glass-air surfaces to provide sufficient contrast before the introduction of lens coatings.

 

[Ian Grant]

Not sure where the Myth of "Less Contrast" comes from Dago's were always good contrast for their date of manufacture, and better than many other lenses with more air/glass surfaces. Certainly on a par with Tessars and sharper overall.

Of course if you compare an old uncoated Dagor to a modern lens then yes less contrast but that goes for any uncoated lens. but compare a coated Dagor to a modern lens and the Dagor is up there close in contrast, certainly mine isn't far behinf my Sironar's and Symmar's at all, and in practice the results are indistinguishable.

Ian

 

[Mike1234]

I wonder why so many people praise them for their lower contrast then. It must be one of those Urban Legends.

 

[Ian Grant]

They say the same thing about single coated lenses, but there's poor and adequarecoating and excellent coating, my mid 50's East German CZJ f4.5 150m Tessar has superb coating although a touch blue for colour work, and is far better coated than 50'/60's Xenars etc and almost as good as Multi Coating.

As David says it depends on the quality/ageing of the optics, older glass was softer so more prone to problems over time so many Dagor's may suffer from lack of contrast but so do Tessar's made of the newer glasses made in the 1930's and many other old lenses.

Lack of any coating does mean softr contrast due to internal flare and most Dago's particularly German are uncoated.

Ian.

 

[David A. Goldfarb]

Also, at wider apertures, Dagors have some spherical aberration (more, it seems, with older versions) that is responsible for the illusion of focus shift that some mention and that causes a little glow, which might also be interpreted as a reduction in contrast. For portraits and still life sometimes that slight glow around f:8-16 can be desirable. To get the wide coverage of a Dagor though, you need to be at f:22 or smaller, which will eliminate that issue.

 

[Mike1234]

I should have realized the contrast/aberation issue is something that changed over time. This is something not always mentioned when describing atributes of a particular lens brand/series. So, if one is looking for those qualities (lower contrast/glow) then they should be seeking the earliest models... makes sense now that I think about it. The latest DAGORS are more like G-Clarons, right?

 

[Ian Grant]

G-Clarons aren't optimised for normal use like Dagors, all Dagor's a re based on the original 1890's design, but optical glass improved over the years so the design evolved but only in the same way as say the Tessar design. So even a late Dagor is still the same fundamental design as the first.

If you specifically wanted a lower contrast model then any uncoated version will fit the bill, but contrast shouldn't be that much lower except when shooting into bright light, etc. I was shooting with an uncoated Tessar and under some conditions the loss of micro contrast was noticeable.

Ian

 

[Mike1234]

Interesting... thanks, Ian.

 

[sanking]

G-Clarons aren't optimised for normal use like Dagors, all Dagor's a re based on the original 1890's design, but optical glass improved over the years so the design evolved but only in the same way as say the Tessar design. So even a late Dagor is still the same fundamental design as the first.


Ian

Just for the record, many of the early G-Claron lenses are of Dagor design, not plasmat. I own two lenses of this type, a 210mm and a 240mm. They are single coated and excellent performers, giving more contrast in fact than single coated plasmat type lenses because of fewer air to glass surfaces.

Sandy King

 

[Steve Hamley]

I should have realized the contrast/aberation issue is something that changed over time. This is something not always mentioned when describing atributes of a particular lens brand/series. So, if one is looking for those qualities (lower contrast/glow) then they should be seeking the earliest models... makes sense now that I think about it. The latest DAGORS are more like G-Clarons, right?

Mike,

No, the earliest G-Clarons are a Dagor design, a 6-glass, 2 group lens, or a lens comprised of 2 cemented triplets. Dagors never changed in the design of the groups while the G-Claron did.

Single coated lenses have more contrast than uncoated, and at least to me, modern multicoated lenses have more contrast than single coated. The effects of coating boosting contrast was mentioned by Ansel Adams in one of his books, and he suggests that development may have to be altered because of it.

Richard Knoppow on the old usenet stated that he felt that "haze", even a little, cut contrast significantly, and based on my experience with old lenses I'd agree. I'm extremely suspicious of any lens with haze. And you see a lot of them because unlike a dead shutter, it doesn't impair you from physically making a photograph, and people will accept haze soooner than a dead shutter. I'd MUCH rather have crystal clear glass and a fixable shutter versus hazy glass and a good shutter, although the latter always seems to bring more when sold. I've seen haze easily cleanable on coated and uncoated lenses, and some that was not. Deteriorated cement or Canada balsam can also have the appearance of haze.

Finally, a lot of people made a lot of Dagor design lenses, in a lot of different barrels and shutters. Internal baffling of a barrel/shutter can produce general flare that significantly reduces contrast, and obviously when you have dozens of companies making a similar design over a hundred years, some will be worse than others.

According to an 97-year old friend who's been in commercial photography for well over 60 years, all lenses will shift focus somewhat when stopped down, and the final focus check should be as near to the taking aperture as possible. Sounds like good discipline in image-making to me.

Cheers, Steve

 

[Mike1234]

That's a nice thorough explanation Steve. I appreciate it as I'm sure the OP does too.

I bought lenses reputed to be both sharp and contrasty. Regarding focus shift, I chose slower lenses to save weight and they're all modern so I hope focus shift will be negligible. BTW, I know this is considered "evil" here but if I want SF (Imagon-type effect) or brighter shadows or whatever I can do that in Photoshop. I prefer to have a "sterile squeaky clean" image that I can work with... I like to keep my options open.

 

[Ian Grant]

Just for the record, many of the early G-Claron lenses are of Dagor design, not plasmat. I own two lenses of this type, a 210mm and a 240mm. They are single coated and excellent performers, giving more contrast in fact than single coated plasmat type lenses because of fewer air to glass surfaces.

Sandy King

My point was more that the G-Claron's are Repro lenses and not optimised for Infinity or normal use,of course there were Repro Dagors to. In many cases that in itself may make little difference but there can be problems.

One problem with any Graphics/Repro lens is they are optimised for flat field work usually at 1:1 and in the case of the G Claron best between 5:1 and 1:5.

While Schneider state they can be used for normal photographic work they state they can be used up to an angle of view of 64 degrees, less than a Symmar or Sironar.

The image circle might be much greater but there are issues of spherical distortion using process lenses at or near infinity. This may be an problem at the edges/corners, obviously some designs will be worse than others.

It's possible that the early Dagor type Claron's are better than the later Plasmat designs in this respect but they still aren't optimised for normal use.

Ian

 

[sanking]

Mike,

No, the earliest G-Clarons are a Dagor design, a 6-glass, 2 group lens, or a lens comprised of 2 cemented triplets. Dagors never changed in the design of the groups while the G-Claron did.

Single coated lenses have more contrast than uncoated, and at least to me, modern multicoated lenses have more contrast than single coated. The effects of coating boosting contrast was mentioned by Ansel Adams in one of his books, and he suggests that development may have to be altered because of it.

Cheers, Steve

Some years ago I owned and used mostly vintage lenses for my ULF work. That included several uncoated Dagors and Protars. When I replaced one of the uncoated Dagors with a modern multi-coated Nikkor M lens I had to decrease development time by about 25% to account for the much greater contrast of the multi-coated lens.

That said, the single coated Dagor design G-Claron lenses are great value. Late model coated Dagors of the same vintage, Kern for example, generally sell for a lot more than the Dagor type G-Clarons, in part I think because not many people are aware of the fact that early G-Claron are in fact Dagors.

As for the ultimate in contrast, try a multi-coated Dagor, say the 14" Kern Dagor or the Schneider 550 XXL. With only four air to glass surfaces and multi-coating you get a very contrasty negative with these lenses.

Sandy King

 

[df cardwell]

There's an exchange between Paul Strand and Ansel Adams, published (IIRC) in AA's Letters.

Strand had his prized Dagor coated after WW2, and it forced him to change his way of shooting: single coating a Dagor (or Protar) removes the flare from the deepest shadows which affectively provided the Zone I density; like a single exposure unit of Pre-Exposure. To compensate, Strand (and all of us since) had to double his exposure. A MC lens might approach a two Zone loss of density compared to an uncoated Dagor/Protar.

The higher up the scale, the less the effect of flare. By Zone III, flare is non-existent. But an uncoated lens is perfectly capable of extremely contrasty results. Only when we compare contrast side-to-side, do we se the difference. If you increase the development, you get sufficient contrast with an uncoated lens fir B&W. Color is a different set of issues.

Then again, coating 'flare monsters' like Plasmats and Cooke Convertibles made them far more useful.

 

[Steve Hamley]

Hey Sandy,

On what formats do you find the 450mm Nikkor M usable for contact printing?

Cheers, Steve

 

[sanking]

Hey Sandy,

On what formats do you find the 450mm Nikkor M usable for contact printing?

Cheers, Steve

The 450mm Nikkor M is a great lens for 14X17, 12X20 and 16X20, if you stop down to f/22 or so. Also works for 20X24 if you stop down to f/64 or f/90, but the corners will be soft.

Sandy