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View Full Version : Info on Voigtlander Collinear F7.7 please



Henry Suryo
21-May-2007, 05:56
Hello, can anyone tell me about this brass lens, it's marked The Voigtlaender & Son Opt. Co., New York. Collinear Series III no. 8 f7.7. Aperture is a modern scale f7.7 to f64. The focal length seems to be about 18/19 inches or so. I'm wondering how this lens would compare to a 19 inch Dagor in terms of image quality, coverage, and value, they are similar in construction, symmetrical cemented triplets with different positive and negative configurations. Any other practical information would be most appreciated, is it overkill to use this lens for the 8x10 format? Many thanks.

Gene McCluney
21-May-2007, 06:29
I don't know what you mean by "overkill". If you need a longer than normal focal length lens for 8x10 then a 19" would be fine if you have enough bellows extension to focus it. Older uncoated lenses are more prone to flare, therefore you should try to shield the front of the lens from the sun when shooting outside. Almost any 18/19" lens should easily cover 8x10 with movements.

Henry Suryo
21-May-2007, 06:52
What I mean is that if the lens has a stopped down coverage of 90 degrees like the Dagor, wouldn't there be a lot of wasted image circle on 8x10, which may or may not cause bellows flare? Like the Dagor, the symmetrical cemented triplet design only has 4 air-glass surfaces so it should be fairly contrasty despite being old and uncoated.

Jim Galli
21-May-2007, 06:57
I've got one too but haven't used it yet. I think it will cover the 14X17. One thing I do note is that the glass and the design of the individual cells is very different from a Dagor in that the cells are physically longish. Dagor's are much more compact. The 19" Collinear may be nearly an inch longer than a Dagor because the glass is so thick. I think that cuts into coverage if you're really going to compare apples to apples.

Uli Mayer
21-May-2007, 11:47
The Collinear Series III (which is quite similar to Steinheil's Orthostigmat) should cover an angle of at least 60° (according to Hartmut Thiele) . Patent numbers are D.R.P. 90482 and 91883. If you want to see its design and specs, go to Eric's marvellous website:
http://dioptrique.info/objectifs/00068/00068.HTM

Moritz von Rohr and others praised the Collinear's and Orthostigmat's performance as being on the same level as that of the Dagor. Main difference: Contrary to the Dagor their cells could be used individually.

Cheers
Uli

Ken Lee
21-May-2007, 12:16
This site can be translated on-the-fly from French to English, using Google.

1) Go to http://www.google.com/language_tools?hl=en

2) Under "Translate", see "Translate a web page". Enter the following URL: http://dioptrique.info/

3) Choose "French to English"

4) Click on the "Translate" button.

Note that Google will translate all text, but some of the items which look like text, are actually images. The home page of the site contains one such image. Just enter the site by clicking on the main image.

I wish I knew more about Optics and Physics.

Uli Mayer
21-May-2007, 12:32
Here is the patent for this lens design:http://www.google.com/patents?id=1GpfAAAAEBAJ&dq=562614

Jim Galli
21-May-2007, 12:50
Uli, the one you show is the non symmetrical like the onyx. The symmetrical like the Collinear is just above in the list at 00067.

Uli Mayer
21-May-2007, 14:12
Thanks,Jim,
I posted it too hastily. But if you compare those two early Voigtländer 6-2 lenses, you'll see that they are closely related by patent numbers. The later one is a supplement.
Just a word of caution - addressed to me as well - because this is too easily forgotten:
The principles of a new lens design are spelled out in the 'claims" whose wording is so confounded that one has to be a patent lawyer to understand them. These claims cover a lot of modifications; a specific lens description in a patent is rarely more than an example given by the inventor. - And no lens maker is obliged to stick to his patents. He can do what he wants, as long as he doesn't violate patents held by others.

Gene McCluney
21-May-2007, 15:36
What I mean is that if the lens has a stopped down coverage of 90 degrees like the Dagor, wouldn't there be a lot of wasted image circle on 8x10, which may or may not cause bellows flare?

This is an interesting statement. I would think that because of the corrugated construction of the bellows, and the inside being non-reflective flat black, the excessive coverage would not be any cause for alarm in regards "flare". I would think that the bellows would just "soak up" the excessive image. I regularly use a 12" uncoated Dagor on my 8x10. And a 12" Dagor will cover 11x14. I get nice snappy images with this lens. Lots of people regularly use 16 to 19" lenses on their 8x10 cameras if they have enough bellows extension with good results. Most 16 to 19" lenses have much wider circles of illumination than is required for 8x10.

You could restrict the circle of illumination of your lens by putting a rather deep lens shade on it.

Paul Fitzgerald
21-May-2007, 18:09
Hi Henry,

according to the 1905 Voigtlander New York catalog the Collinear III #8 f/7.7 is 17inch focal length, covers 14x17 at f/7.7, 16x18 at f/16 and 18x22 at f/32. The rear cell can be used seperately as twice the focal length as f/16.

Hope it's a help.

Darren Kruger
22-May-2007, 14:58
"A handsome camera deserves a perfect lens, for only such can produce proper results."

From an advertisement from the December 1899 issue of "The Photo-Miniature"