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View Full Version : Goerz Barrel Lenses: Flange Sizes



David A. Goldfarb
13-Nov-2001, 07:50
I discovered the happy coincidence that my Goerz 12"/f:6.8 Gold Dot Dagor and 19 "/f:11 Apo Artar, both in barrel, use the same flange, so I'm having Steve Grime s make me an adapter to mount either lens on the front of an Ilex #5 shutter (fa ctory mounted, these lenses would have come in an Ilex #4, so the #5 should leav e enough room for a front mount without vignetting).

Since I'll have this adapter and barrel lenses are cheap, now I'm wondering what other lenses might be able to use this same adapter. Any Goerz collectors know the answer?

Jeff Buckels
14-Nov-2001, 12:28
David: Probably my Goerz R18 eighteen-incher. This lens is the same thing as an 18-inch Red Dot, and was marketed for some industrial purposes or other.... BTW, in case anyone is interested: The proper noun Goerz should be pronounced "gertz" (reasonable English pronunciation). I've always assumed this, but the other day was startled to hear the quite knowledgeable proprietor of a serious local photog store say something like "gortz". I called my brother in law, a native German, and he said it's "gertz". Anyone know any different? -jeff buckels (albuquerque)

David A. Goldfarb
6-Dec-2001, 17:30
Reporting back, since some people asked how this front-mount adapter system worked out.

With these two lenses--Goerz 12" Gold Dot Dagor and 19" Apo Artar on an Ilex #5 shutter--it's a good solution. Loads of room for movements, and I get bellows impingement before I can see any vignetting from the shutter flange.

I'm trading some speed in setup time with this arrangement, and tilts are slightly more complex, since the tilt axis is now further from the nodal point of the lens, but now I can carry three or more lenses into the field (the shutter originally contains a 10" WF Ektar) with only one bulky shutter and lensboard. This also invites some risk, because if the shutter jams, I'm out all the lenses that use it, but it's a risk I can take in many cases for the advantage of having more lens options. I might not carry so many lenses if each had its own shutter, and I'd still be risking mechanical problems.

David A. Goldfarb
6-Dec-2001, 23:15
I asked a collector about my original question, and he said I probably got really lucky in finding two Goerz lenses that use the same flange, in that some Goerz lenses of the same type and focal length of different periods don't even use the same flange. He though my best bet would be a 10 3/4" Dagor, but that's not really a focal length I need. I'll still keep an eye out.

Robert A. Zeichner
7-Dec-2001, 08:31
On additional advantage of front mounting is that if you test your shutter and record the resultant adjusted speeds, you will have three lenses with exactly the same shutter speeds. I imagine that would be especially helpful if you were shooting transparencies.