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View Full Version : Old Brass WA lenses for 8x10. Tell me what I have.



PHOTOTONE
02-19-2007, 09:08 PM
I have three teeny-tiny brass wide angle lenses that are marked as being for 8x10. These are barrel lenses, no shutter. Never had shutter. Would anyone think these might take decent b/w photos?

Two of them have stop wheels you turn to set aperture stop, various size holes on a rotating disc. The final one has a conventional iris diaphram.

There are two almost identical lenses.

One says:

J. C. Somerville St. Louis Mo 3726 8x10 No. 2
this one has a stop wheel with stops from 16 to 512

Another almost identical one says:

Schiller Extreme Wide Angle Anastigmat 8x10
this one has a stop wheel with stops from 16 to 256

And a larger one with iris diaphram..still brass though:

Seneca Camera Mfg. Co. Extreme Wide Angle 8x10
The iris is from 16 to 256

Any advice or information on these would be appreciated.

Harrigan
02-20-2007, 07:47 AM
I use alot of old brass wa lenses. I cant say without at least seeing a pic of the lenses but the non anastigmats are most likely wide angle rectilinear (war) lenses 4 elements 2 groups. These can be used for soft effect wide open as the image rapidly softens up in the corners or you can get nice fully sharp images if you stop the lens down to around the modern equiv of f64 and contact print.

The anastigmat is probably a better corrected lens than the other two and should make fine landscapes or whatever. These lenses are uncoated and will show some flare. You can not compensate for flare but you might want to use a red filter or increase dev times to add some contrast and try and use a lens shade.

Murray@uptowngallery
02-21-2007, 02:11 PM
Jim Galli (tonopahpictures.0catch.com) [that's a zero in front of 'catch') may know details on them too.

Harrigan mentions modern f-stop numbers - I suspected those nubers were probably 'USA' aperture numbers, predating f-stop numbers.

I think USA 16 = f-16 and the USA sequence is by diameter (factor of 2)rather than area (factor of square root of 2)...

so (I hope I have this right)
4 = f/8
8 = f/11
16 = f/16
32 = f/22
64 = f/32
128= f/45
256 = f/64
512 = f/90

Ole
02-21-2007, 02:20 PM
I thought I had answered this already, but that must have been on another forum. :D

Anyway, and additionally, it's the "US", not "USA". It's an abbreviation for "Universal System", which of course means it never even achieved global acceptance.
It didn't "predate the f-stop numbers", but instead was one of several concurrent systems in use. Among them were F-numbers, the Stolze system, US, and several others including arbitrary numbers and the diameter in mm.

Apart from that, I agree with Murray: I'm sure those stops are in US.

And his table is correct, too! :D