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Alex mckay
15-Jul-2004, 12:59
I have a EKC, Eastman Kodak Company B&L 1910 lens with a US aperture system. I showed it to Sam Vinegar of Classic Camera, Grosse Pointe MI, 15 or 20 years ago and he told me there were several systems competing for the market and the one we currently use won out. He provided me with a conversion chart that I have since lost. Anyone out there have such a chart? And, in regards to my Conley triple convertible lens, 1907, how do I know if an aperture system on an old lens is our current one? Also Does anyone out there know if Sam Vinegar is still in business?

Deniz
15-Jul-2004, 15:07
I used to wonder the same for my B&L lens from late 1800s and they helped my out. check out the link http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=008856

Donald Brewster
15-Jul-2004, 15:56
Don't know about Sam Vinegar, but I believe Classic Camera is still in business. Have two addresses and don't know which is current.

Classic Camera 20219 Mack Grosse Pointe Woods, MI 48236 313-884-2242

Classic Camera 22720 Woodward Ave. Ferndale, MI 48220 248-591-7433

Ernest Purdum
15-Jul-2004, 18:31
"U.S" stands for Uniform System, which means that double the number means you need to double the exposure. The system starts at U.S. 1, which is f4. U.S. 2 is f5.6 and U.S. 4 is f8, which explains why so many old Folding Pocket Kodaks with Rapid Rectilinear lenses are claimed to have f4 lenses. U.S. 8 is f11. U.S. and f16 are the same. U.S. 32 is f22. U.S. 64 is f32. U.S. 128 is f45. This is as far as the system is usually carried.



Regarding your Conley, if the system used isn't identified, you can tell by the progression. If it is all in even numbers which become very large at the small aperures, it is the Uniform System.



There were indeed several other systems used for awhile, and also the "Continental" numbering series, which are f numbers like we use today, but a third stop off the common ones. f4.5 is one of the numbers of the Continental series.

jnantz
15-Jul-2004, 18:55
ernest :

do you know anything about the stoltz system?

i used to have a tiny little brass 58mm lens that covered 4x5. dagor77 helped me id the aperture system as the stoltz system. i have never seen another lens with this system ( going on 20 years ) ...

much thanks!

-john

Ernest Purdum
15-Jul-2004, 21:29
John, Offhand, I can't come up with anything. My recollection is that the spelling is Stolze, but I could be wrong. Your mention of a "tiny little lens" rings a bell, because I think the system was intended for use with magnified subjects.



I'll keep looking and let you know if I find something helpful.

jnantz
15-Jul-2004, 21:54
hi ernest ...

thanks! that would be great ... your spelling sounds right to me too ... im a reel bad speller.

-jhon

Erik Sherman
16-Jul-2004, 05:44
The Stolze system is apparently also called the European scale. Here's one link:

http://mejac2.palo-alto.ca.us/leica-users/v01/msg03116.html

I can't vouch for its accuracy, but at least it's something.

Jason Greenberg Motamedi
16-Jul-2004, 08:02
I have NO idea where this chart is from, but I posted it on photo.net, perhaps it will be of use:

http://www.photo.net/photodb/photo?photo_id=2531428

Dan Fromm
16-Jul-2004, 08:30
About those tiny little lenses, Ernest, I've had a number of macro lenses whose aperture scales seemed to indicate the diaphragm's diameter in mm.

They include: 45/4.5 CZJ Mikrotar (pre-WWII, it seems); 50/3.5 Reichert Neupolar; 90/6.3 CZJ M (postwar, coated); and two 100/6.3 Neupolars. A borrowed postwar 45/4.5 CZJ M that was coated and not the same design as the Mikrotar had the same style of aperture scale.

All of these lenses have aperture scales that run from a small number (1 on the 90/6.3) with the aperture at its smallest up to a larger one (16 on the 100/6.3s) with the aperture wide open. TTL metering on a Nikon is consistent with my interpretation of these lenses' aperture scales.

Yours for the spread of confusion,

Dan

Ernest Purdum
16-Jul-2004, 17:16
I couldn't get Eric's page to open, but the page Jason contributed looks familiar and I think it is the one I was searching for so I'll stop looking. I notice down in the lower left corner the word "Englisch", so apparently the chart is from an English translation of a German original. J.M. Eder's Handbook of Photography would be my first guess. I have a copy, but not at hand. Many years ago, I constructed a chart showing these systems and more and nearly drove myself batty doing it. You'd think I would then have carefully preserved a copy of the publication it was printed in. Well, maybe I have it somewhere.



Jason, computers are weird. On my screen your chart is black, but it prints green. Thanks for providing the answer.



Dan, sometimes the barrel for a set of convertible lens cells will be marked in millimeters also. The chart that goes with the set is usually lost, of course, joining all the Waterhouse stops and single socks. I suspect that instruction sheets for your lenses probably existed but have met the same fate.

jnantz
17-Jul-2004, 18:49
thanks jason!