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Bill_1856
6-Jun-2006, 12:02
I've always had a soft spot in my heart (head?) for Dagors. I have several postwar coated versions (120, 150, 210), but have never been able to compare them directly with modern coated/multicoated Plasmats. I know their coverage is awesome, but how about the resolution and contrast both in the central field and corners? Thanks.

sanking
6-Jun-2006, 13:11
I've always had a soft spot in my heart (head?) for Dagors. I have several postwar coated versions (120, 150, 210), but have never been able to compare them directly with modern coated/multicoated Plasmats. I know their coverage is awesome, but how about the resolution and contrast both in the central field and corners? Thanks.

Dagors are wonderful lenses and are competitive with modern plasmats in terms of resolution, provided that you close them down to at about f/22 and don't push the coverage beyond about 80 degrees. That is really pretty incredible considering tht the design is over a century old.

Single coated coated Dagors are more contrasty than single coated plasmats, and multi-coated Dagors (late Kern Dagors made in Switzerland) are among the most contrasty of any lenses ever made. Even uncoated Dagors are quite good since with only four glass to air surfaces transmission is around 88%.

BTW, some of the early G-Claron lenses are of Dagor design, or at least of very similar design, and I have a 210mm version of this lens and love the results on 5X7. Got the lens in trade from our good friend Jim Gali.

Sandy

Ole Tjugen
6-Jun-2006, 13:16
Some of the early Symmars are Dagor design too - the triple convertible ones are. Then they changed to Plasmat for the single convertible.

I happen to prefer Plasmats - YMMV.

Dan Fromm
6-Jun-2006, 15:02
Bill, I can't answer fully because I shoot 2x3 and the lenses in question are 210s that cover much much more. But I just shot a 210/7.7 Boyer Beryl S, dagor type supposedly optimised for 1:1, against a 210/5.6 Boyer Zircon, plasmat type. Both single-coated. The Zircon has poor front coating, traditional cleaned with steel wool appearance. At ~ 5 m they shot about equally well from f/8 down. On 2x3, one could be happy with either. Probably a little happier with the Beryl S, it is smaller and lighter.

Jack Flesher
7-Jun-2006, 22:09
Well today I took delivery of my first Dagor -- a 14-inch Gold Dot, Kern multi-coated version. I just finished mounting it up on a board so I can test it out tomorrow with the Betterlight. I'll post my initial impressions after I see the files.

I must say at the very least it's pretty to look at, a work of art in its own right. Up there with my Cooke :)

Sheldon N
7-Jun-2006, 22:21
Well today I took delivery of my first Dagor -- a 14-inch Gold Dot, Kern multi-coated version. I just finished mounting it up on a board so I can test it out tomorrow with the Betterlight. I'll post my initial impressions after I see the files.

I must say at the very least it's pretty to look at, a work of art in its own right. Up there with my Cooke :)

Both myself and a friend were watching that auction as well. Glad it went to a good home, and at a much cheaper price than the $3k the other seller was asking for their Kern Dagor!

Let us know how it performs.

Jack Flesher
8-Jun-2006, 18:25
My initial Kern Gold Dot impressions are now posted over in the lens forum: http://www.largeformatphotography.info/forum/showthread.php?p=163336#post163336

Steve Hamley
8-Jun-2006, 19:40
I have a bunch; here's the dope

There are Dagors and then there are Dagors. Jim Andracki at MPEX, who has handled and shot more lenses in a month than most of us will in a lifetime said the Schneider Kern Dagors are softer and cover much less than the American Goerz Dagors. The lesser coverage seems to be gospel, how much less is debatable. A 14" lens needs about 73 degrees of coverage to cover 8x20, yet the almost universal opinion is that a Kern Dagor will not cover, hence less than 73 degrees.

My 14" Kern Dagor is slightly soft wide open, and extremely flare prone into the light, which was a surprise for a lens with 4 glass-air interfaces. I can't let direct light shine on this lens; it has to have a shade to come anywhere close to its potential. It's a single coated example in an early chrome shutter. Glass and coating are perfect, no haze. I'd trade it for a perfect 14" Goerz Gold Dot or Gold, maybe even a regular late coated.

12" Goerz Gold Dot that's simply superb by any standard. It's on the never sell list. I wish I had a 10-3/4" just like it in image quality.

9-1/2" f:11 Goerz Argyle (made for an Argyle process camera) that's a Trigor (wide angle) copy, and it's a bit soft wide open, actually about f:8, on the GG at infinity, but as sharp and contrasty as anything stopped down f:16 and smaller. It's especially good up close as you would expect. 10 grams lighter than a 240 Germinar W. Shoe horned into a Rapax shutter that's a bit larger than a Copal 1 by S.K. Grimes, probably wouldn't do it over again considering the cost.

9-1/2" Gold Dot in Copal 3 that's indistinguishable in image quality (color and contrast) from a 270mm G-Claron in Copal 1 shot side by side.

19" Goerz f:11 Series IV Double Anastigmat. Uncoated, couple of scratches on rear glass, some internal cement haze, image quality simply extraordinary. Can't explain it. It's now in a "small" 56mm Copal 3, transplanted from an even smaller Compound #3, takes a 58mm filter, covers 20x24 wide open according to Tracey Storer. Killer solution for a rickety 8x20 Korona. Never sell.

16-1/2" Series III Dagor, brass barrel, uncoated, on loan and hope to buy. Nice lens, some internal haze in front cell. Lens has won awards by professional photographer. Covers 12x20.

Kenro K2, Goerz 270mm, 10-3/4" process Dagor, in barrel. Sharp and cheap. I have 2, both are sharp as can be. Would have to be custom mounted into Copal #3 or Ilex #4. In shutter, expensive and large compared to a 270mm G-Claron.

Kenro K, 8-1/4" f:6.8, untested but expect great things.

Goerz American Optical K1, 6" process Dagor, barrel, illuminates 8x10 with some mechanical vignetting. Amazing that it would even illuminate an 8x10 GG since the glass is the size of a dime.

Goerz 6-1/2" Gold WA Dagor. Fits in your shirt pocket, covers 10x12 stopped down. What else to say. Never sell.

8-1/2" Gold Dagor: Nice lens, covers 8x10, but can't be used with a Lee filter system because the glass is just too close to the shutter to allow adjustments of aperture and shutter speed with the filter in place.

I have a couple of other odds and ends, but I think the previous long and tedious narrative confirms what others have said; early Dagors are a crap shoot with varying quality. A good one is as good as it gets, coated or uncoated, some have exceptional image quality, others are indistingushable from modern equivalents. The only thing you can do is buy and sell a lot of them keeping the best.

Just a final comment, (most) Dagors are not rare, but they are pricey for what they are. If you're wanting a one-shot wonder, get a modern lens. Buy 12 "Dagors" from 1901 to the latest Kern, and you'll have 3 you won't part with, 2 dogs, and the rest undistinguishable from other decent lenses.

Steve

Jack Flesher
10-Jun-2006, 09:41
Steve:

I have a question re newer Dagor sharpness. I understand from my repair tech that cell spacing is uber-critical on dagors and it is always best to get one in its original shutter. Can you comment?

Steve Hamley
10-Jun-2006, 15:30
Jack,

It's been my experience that many of the Dagors have process counterparts that are always quite a bit shorter. For example, My 14" Kern Dagor is quite a bit longer than a friend's Kern Trigor, same for the others that I have process counterparts to such as the 8-1/4" and 9-1/2" versions. About 0.060" difference in the shorter ones off the top of my head.

So I'm not sure that's true, but it does appear they used spacing to adjust the optimization of the lenses, process lenses are always shorter.

I think any lens needs to have the correct spacing to perform as the manufacturer intended, but I'd actually think that a Dagor, being symmetric, would suffer less from slightly incorrect spacing than a non-symmetric lens. The measurements I've noted on three examples versus their process counterparts tend to support this within reason. No doubt just putting cells in a shutter that was 1/4" off (especially too long) would be likely to have serious effects.

Steve