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Andrew_3677
3-Jun-2004, 11:29
I have both the front and rear cell for a 7" goerz double-anastigmat (seriesIII no.2)....i dont have the barrel for it..just the cells. the lens threads are 45mm, any ideas on what kind of shutter i might look out for to put these in? does anyone else have this lens? wondering how theirs is mounted?

thanks -andrew

Donald Brewster
3-Jun-2004, 13:27
I'd suggest looking at http://www.skgrimes.com or giving them a call.

Jim Galli
3-Jun-2004, 14:24
I have a later 7" Am. Opt. Co. Dagor serial high 7xx,xxx, coated that is in an Ilex #3 shutter via machined bushings that adapt the lens cells to the shutter.

Andrew_3677
3-Jun-2004, 15:38
Jim, does your 7" cover 8x10? yours is a 6.8 isnt it? mines is too. Do the bushings look like they control the spacing of the cells from the aperature or are they more like just adapting thread sizings (that is, with the bushing does it screw in flush to the front of the ilex? or does it look like its raised a bit ot sunk a bit?)..hope that makes sense.

Is it possible to find lens cell spacing specs for lenses anywhere?

Ernest Purdum
4-Jun-2004, 15:52
Andrew, since your cells are marked Double Anastigmat Series III, rather than "Dagor" it appears that they were made before 1904, the year in which the Dagor name came into use. This means that they would have most likely been either in a barrel or in Goerz"s own "Sector" shutter. The Sector is the one that has two tubes protruding straight down from the bottom with a cocking plunger in between. They were made of aluminum (very expensive then).



Re-mounting cells into shutters from other sources seems to have been rather common at the time, but this would have involved adding threaded bushings like the one Jim Galli mentioned. Folmer & Schwing charged a whole extra dollar to do this work. Jim's Dagor/Ilex combination may have been put together at Burke & James who performed many marriages of this sort in later years.



Regarding your question about finding lens spacing specifications, I have never seen any compilation of the sort, and rarely seen any information on any one lens, although questions on the subject come up fairly often.

Jim Galli
5-Jun-2004, 11:40
Hi Andrew. Better late than never. I don't think every mounted Am. Opt. Co. Dagor was a product of Burke & James. I think this one is factory done. In any case, to answer some of your questions: Yes it is the f6.8, and yes it appears it would just cover 8X10 at f45 if you needed it to in a pinch. I've never used it on the 8X10. The 2 cells on this later vintage lens are threaded about 37mm and are fairly tiny. If I had the $ they could easily go into a modern Copal 1, so they're different from yours. The 2 bushings very definitely are controling the spacing to the aperture. They are different from each other and the front bushing "recesses" the cell in past the edge of the bushing to make it closer to the aperture while the rear bushing actually has a little boss that holds that cell farther away from the aperture. Cell spacing without the original barrel is going to be a crap shoot at best unless you have either some origianl specs or a sophisticated optical bench. Hope this helps. If someone has a series III in original barrel, how about helping out and removing the cells and measuring with a caliper.

Struan Gray
5-Jun-2004, 12:37
I have a 124 mm Series III Berlin Dagor in a barrel mount with a slot for Waterhouse stops. The admittedly slightly vague provenance I was given dates it soon after the 'Dagor' name began to be used. Mine has no rear cell - the elements behind the stop position are mounted directly into the barrel - but a Vernier caliper used very cautiously says 22 mm from vertex to vertex. The various distances should scale linearly with focal length, so if you get no other leads you could use my spacing as a starting point.

Richard Knoppow who haunts rec.photo.equipment.large-format is a fount of wisdom on all matters Dagor, so you might try posting there.