Coverage of this particular dagor

[Former Member 8144]

Hi all,

I'm looking at buying Eddie's 8 1/4 inch dagor but I'm trying to find out the image circle to see if it will cover 8x10 with some movements.
Eddie knows I am posting this topic.

So it's an 8 1/4 inch F6.8 dagor.
Serial number is 756...

You can see the actual lens on eddies for sale post.

If anyone has used this version of this dagor lens on 8x10 can you let me know what the IC was like.

Thanks for the help,

Marc

[CCHarrison]

IF you check out the Goerz ads on my page here

http://antiquecameras.net/1904goerzlensads.html

You'll see the 8 1/4 covers 8x10 "sharply", but not until f/62

Dan

[IanG]

Dan, my Goerz Am Opt data from a Gerz catalogue shows the 8¼" as covering 5"x8" at f6.8, 7"x9" at f16 and 10"x12" at f45. That means the lens should be covering 10x8 by around f22/f32.

I'd add that the same data for the 12" matches the performance & coverage of my own Dagor.

Ian

[Robert Hughes]

For some reason, I'm reminded of that Jimi Hendrix song about the photo-taking groupie... Dolly Dagor! :p

[CCHarrison]

Hi Ian,

I dont doubt you, but I am just reading from the specs in a 1904 catalogue. And note, that it states to 'sharply' cover 8x10 it needs f/62...

Dan

[IanG]

Dan, I suspect the Dagor was improved as new glasses became available, both sets of coverage figures we've referenced come from Goerz themselves.

By 1913 Goerz AM Opt where showing the Dagor 8¼" as sharply covering 10"x12" at f32, using exactly the same wording "size of plate sharply covered".

It would be interesting to see how much difference there is in practice between the very early Dagors and later lenses.

Ian

[eddie]

i believe the later dagors covered a bit less as the design may have be changed slightly and the shutters may have cut the coverage as well. the series III brass lenses cover way more than the others.

[Jan Pedersen]

Marc, Ian and Eddie got it right, the "Modern" Dagor has less coverage than the older series III lenses.
Whether the serial number is in the 75xxxx range or above 77xxxx makes no difference except that any Dagor with a serial number bellow 77xxxx is not coated unless it was custom coated.
I did quite a bit of testing of my 210 Dagor and a Fuji 210 (Old Model with 352mm IC and found the Dagor a much better performer, particularly at infinity where the Fuji is a dog. As far as corner sharpness with both lenses, i can't tell since i contact print on 8x10
I have 4 Goerz Dagor lenses, all coated some with some gold and some not. One day i will be shooting with nothing but Dagors.
They are stellar performers. Some will disagree. (I know a few)

[ljsegil]

The uncoated Goerz DA III 210/6.8 is a beauty, covers 8x10 in good health, and can light up a scene like nothing else that I know when you hit its magic spot. To take nothing away from Eddie's lens, a venerable special in its own right.
DA III scene attached (shot wide open at f/6.8, late afternoon sunlight).
Larry

[Former Member 8144]

That's a very painterly image..just my cup of tea!

So is the DA III an earlier version of this lens?
Do they have specific marking on them..i.e. DAIII or do you just need to know by serial number etc?

I've had to put off my lens purchase for a few weeks but good to know what are the good options in the wide end of 210-250 spectrum.

Marc

[ljsegil]

There are far better lens historians on this forum than I who will hopefully chime in and correct my errors here, but the Goerz DA III is an abbreviation (unofficial, my laziness) for the Goerz Doeppel (?sic) Anastigmat Serie III 210mm f/6.8 lens that Goerz manufactured prior to deciding to use the acronym Dagor (DA Gor) to distinguish their lens from the many other double anastigmats (I believe the Zeiss Protar Series VII would be an example) available at that time. As history testifies, the Dagor acronym stuck, right down to the present time which I believe is thirty plus years since the last Dagor left the shop (I believe Schneider was the final owner of the remains of the many incarnations of Goerz Optical). Thus, the Doeppel Anastigmat Serie III precedes the Dagor, but is its direct optical antecedent (again, someone please correct my limited command of the history if I have it wrong), though I do not know whether the earliest Dagors were optically modified from the Serie III or merely relabeled. I also don't know what sort of coverage Goerz claimed for the DA III, but the above example was shot at f/6.8 and although it shows some (not offensive to my not easily offended eyes) vignetting, it is certainly sharp to the corners. Stopped down the lens covers 8x10 sharply and without vignetting, and given my uses for it (no architecture or other serious bellows bending shots) I have not found myself running out of movements. The Serie III were uncoated lenses, could be found in barrel or shutter (I believe factory mounted) and in a variety of focal lengths (I have squirreled away 130mm and 300mm samples which await their turns on the camera--although I tried the 130mm on 5x7 and it does not cover, it hasn't had its chance on 4x5, and the 300mm trial has simply been superseded by other experimental projects; its time will come, soon I hope).
Hope that helps, always happy to muddy what ought otherwise to be a sharp view through previously clear water. Some of the articles on classic lenses on the home page may also shed some light through the murk, as might the material at cameraeccentric.com.
Enjoy your lens, she should make some lovely images.
Larry

[Former Member 8144]

Thanks Larry,
That is an amazing amount of detailed information.
When looking at putting together my 10x8 kit I was thinking of ultimate sharpness, etc but the more I think about it the more I like the idea of shooting with a lens that will bring it's character to my projects...and the painterly look of these older lenses may just be the right thing.
I'll have to keep a look out for one of these dagors or something similar.

Thanks,

Marc

[CCHarrison]

More on the Dagor Series III from the book; Complete Self-instructing Library of Practical Photography‎ - 1908

"Goerz Dagor.—P. 6.8 (Series III.) Universal extra-rapid lens for landscape, architectural, portraits, groups, instantaneous photography, interiors, and scientific work of all kinds.

Although it is but a few years since public attention was first attracted to the Goerz Double Anastigmat Dagor (Series III.), these lenses have won the most extended recognition, not only from authorities in photographic optics who have been in position to exhaustively test their merits, but from the photographic confraternity at large, whether amateur or professional.

The Dagor lens is a universal instrument in the full sense of the word, and comes as near being an all around lens as can be hoped for, considering the manifold and complex requirements of the photographic craftsman.

Each Goerz Double Anastigmat Dagor supplies 1st. A rapid lens for general purposes—portraiture, landscape, architecture, enlargements, etc., working at full aperture with extreme sharpness to the edges of the plate for which it is constructed. 2d. A wide angle lens for interiors and all views at short distances, sharply covering a much larger plate when smaller apertures are employed. 3d. A long focus lens for distant objects, when the back combination alone is used.

Characteristics of Dagor Lenses.—The astigmatism is completely corrected, with the result that, even at full aperture, the image is as sharp at the edge as it is in the center.

The curvature of the field is eliminated within an angle of 72 degrees—i. e., that part of the image which is comprised within that angle is absolutely flat. The definition and depth are the same in all parts of the field.

It is, besides, spherically and chromatically corrected for the axial and oblique pencils, even with the largest stop.

The Dagor lens is free from internal reflections and the image produced is accordingly brilliant and free from flare.

The two combinations are placed in close proximity; consequently, there is no falling off of the luminosity toward the edge, and the entire surface of the image is therefore uniformly illuminated. The compactness of the Dagor lens renders it extremely rigid and portable.

As a result of the symmetrical arrangement of the two combinations of the lens, either may be used as a single landscape lens, the focus of which is about double that of the entire combination.

The Goerz Dagor (Series III.) as a Wide-Angle Lens.—The exceptionally fine correction of the Goerz Dagor lenses over their entire light circle allows us to use them with the most perfect results as wide-angle lenses up to an angle of 90 degrees. They will give critical definition over the whole image subtended by this angle, when stopped down to U. S. 16 (=f. 16) or smaller. Their considerable luminosity at full aperture facilitates focusing materially, for which reason alone this type of objective is greatly preferable to the ordinary W. A. lenses. Furthermore, the angle they include is equal to that provided by most wide-angle lenses stated to give 100 degrees or 110 degrees, and are free from distortion. Though it be true that some lenses have a light-circle of this extent, they do not utilize it on the plate, being not sufficiently corrected to make their full angle available. An actual image angle of 60 degrees to 65 degrees is usually the maximum they produce."

Dan

[CCHarrison]

From October 1912 Popular Photography - Issue # 1 Volume #1 !!

"GOERZ LENSES AND CAMERAS

Probably almost every amateur photographer has heard of the Goerz Double Anastigmat, "Dagor" or Series III, as it used to be called. Last summer the parent firm in Germany celebrated its twenty-fifth anniversary, and at that time it was stated that over 300,000 Goerz double anastigmats had been sold. To many workers, anastigmat is synonymous with Goerz, owing to the fact that one sees these lenses everywhere on cameras and kodaks. The increase of speed from f8 (that of a rapid rectilinear) to f6.8 is sufficient to allow snapshots under conditions which are beyond the scope of the rectilinear, and as the Dagor has a very large fiat field and gives microscopic definition over the whole plate, it may be used with large stops when the rapid rectilinear has to be stopped down to cover the corners sharply; hence the usable speed is greatly in excess of that of most lenses ordinarily furnished with cameras. The special advantages of the Dagor include the following points: It may be used as a wide-angle lens on a larger plate when slightly stopped, say to f16 or f22; the rear half may be used by itself as a landscape anastigmat with a longbellows camera; its aperture is large enough for the photography of moving objects with fast shutters, and yet not so great as to sacrifice depth of field—in short, it is almost universal in its scope, particularly for amateur work. The Goerz cameras cover the field from the miniature pocket camera to the large speed camera with focal-plane shutter."

Dan

[Dan Fromm]

Propaganda, all propaganda. If you want to know what a lens will do for you, don't ask the salesman, ask the lens.

[CCHarrison]

Hi Dan,

While I respect your knowledge and experiences, your post seems to suggest propaganda (or ads as they are commonly known) serve no useful purpose. I think they do, especially regarding coverage. If the manufacturer states a lens will cover 8x10 at f/16, for example, I'd bet it wont cover any more than 8x10 and in fact may (or probably) cover less, perhaps 6.5x8.5 at f/16. Propaganda (ads & reviews ) serve as "best case" scenarios in most circumstances...not much different than Canon making MTF charts available for all of their lenses... I doubt the average user will reach those MTF levels in the "real world." If I understand that those charts are "best case" I can start to set my expectations properly... Ads, reviews and 'propaganda' are all at least a place to start :)

Hell, Pop Photo, Shutterbug, Modern Photog all made businesses out of 'propaganda' !!

Thanks
Dan

[Dan Fromm]

Dan,

I'm very sensitive to manufacturers' coverage claims because of discussions -- the news is in our article on Boyer lenses on the French LF site -- with Eric Beltrando about Boyer lenses' actual coverage. Understand, he loves his Beryls and I like mine, but he insists that Boyer's claim that they cover 85 degrees is a considerable exaggeration. 70 degrees, he says, for most applications, only 50 for stringent ones that require low distortion. Beryls are Dagor types whose prescriptions are close to Goerz patents.

What I meant so say was, and should have said more clearly, is that manufacturers' claims are not safe to act on. All newly purchased lenses, new or used, should be put through acceptance testing before being used in earnest. One can't assume that it is safe to accept coverage claims.

To defuse this a little, take a look at Schneider's published MTF curves for Xenars. They make it clear that Schneder's coverage concept is "coverage ends where the MTF is 0.0." I'm not sure that most of us really believe that, even though there are many posts on this board to the effect that "the lens covers axb, although the corners are soft." Covers? Come on.

Yours for more and better skepticism,

Dan

[CCHarrison]

I think we agree :)

And, how about MPG figures published by auto makers? If you can get within 10% to 15% of their "optimal" figures, you're lucky...

Dan