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S. Preston Jones
29-Feb-2004, 20:11
Can someone who has used a Goerz 111 WA Dagor give me the coverage of this lens? One source I read indicates it only has enough coverage for 4x5 with some movement and in another source it was indicated that it can be used on 5x7 with movement. Please give me your experiences. Thank you

Robert A. Zeichner
29-Feb-2004, 20:49
Hi Preston, I looked at an old Goerz Optical comparison chart and found your 111mm f8 which is listed as covering 5x7. No image circle spec. though. Now if it were an Artar, I could give you all the plate diagonals at various magnifications.

Jason Greenberg Motamedi
29-Feb-2004, 21:29
According to the specs I have (circa 1955) the lens covers 70 at f/8 (155mm), 80 at f/22 (186mm), and 100 at f/45 (265mm). This appears to be pretty accurate with my experience: my 4 3/8" WA Dagor will cover 5x7 at f/32, and at f/45 has about an inch of movement.

wfwhitaker
3-Mar-2004, 16:17
I thought this post looked pretty interesting as I have a 111mm WA Dagor and figured that mounting it to the 11x14 would really put it to the test. So that's what I did. And the result is interesting.



I was expecting to see a fairly well-defined circular image on the 11x14 ground glass. What I got instead was a lot of image! There was no sharp delineation of the image field. The image continued out to the edge of the 11-inch dimension of the ground glass (short side of the format). As you can imagine, a 111mm focal length lens is pretty short for an 11x14 camera. The main problem was with the bellows getting in the way and obstructing the image. I never was able to get the bellows completely out of the image, so I couldn't observe how the illumination dropped off along the 14-inch dimension of the ground glass.



While I was able to see an image circle of upwards of 11 inches, it in no way looked completely usable, at least not critically usable. At f/8 (wide open) the image seemed to show a drop off in illumination at about 3 - 3 1/2 inches from center (the ground glass has 1-inch grid lines). This was strictly a visual inspection and somewhat subjective. But it does correlate well with Jason's post indicating a 155mm image circle at f/8. It also suggests 5x7 coverage, as in Robert's post.



Stopping the lens down helps the coverage, of course. But it's very difficult to judge coverage with the dim image. Furthermore because the light strikes the ground glass so obliquely, it's all the more difficult to evaluate. But even at f/8 there is a lot of image well beyond the first hint of fall-off. No doubt corrections suffer as well that far out. But for the first time I wished I had a bag bellows for the 11x14! It would be fun to make some really wide images on that format, even if they weren't perfect. Assuming the full format, that would approximate an 11mm focal length lens on 35mm!



Best,
Will

wfwhitaker
3-Mar-2004, 16:19
The above was at infinity focus.

-Will

S. Preston Jones
3-Mar-2004, 21:09
Thanks to all of you for your help. I do a lot of work with 5x7 and wondered if it would be worth it to look for this lens. I am interested in getting smaller and lighter lenses. I now have a 90mm f4.5 Rodenstock Grandagon and while I like it, it is too bulky to take into the field. I will now look for the 111mm Dagor. I would love to get the 110mm Schneider SS but it is so costly.

Jason Greenberg Motamedi
3-Mar-2004, 22:13
For what it is worth, I recently bought a 121mm Super Angulon, and have been comparing it to my 4 3/8" WA Dagor for use with 5x7.

The difference in bulk is pretty amazing, however the weight difference isn't actually all that much, since my Dagor is in a Ilex no. 3, a very heavy shutter, and the SA is in a Copal no. 0. In use, what really stands out is not the difference of image circle (both are more than ample), but rather working aperture. With the Dagor, and 5x7 film I am always at f/45, while with the Super Angulon, I can work at f/16.