Goerz Artar 14-inch f9: Anyone Know Filter Size?

[rguinter]

Greetings:

I hate to ask such a simple question. But I'm looking to buy a step-up ring for a few bucks to fit my vintage Goerz 14-inch Apochromat Artar. It is in an Acme No.4 shutter.

I haven't used this lens in a while but now that the spring foliage is coming out I have a few shots that I would like to use it with my 67-mm infrared filters et.al.

My precise measurement indicates 46.6 mm ID (thread to thread). So I seem to think 47-mm threaded filters and step-up rings are the right size.

Can anyone confirm before I order parts?

Many thanks. Cheers. Bob G.

[Kirk Fry]

It is called Magic Goerz size. Proprietary. The size you measured is probably it. They used some goofy size not intended for filters. That is what the slot in the side of the barrel is for (but you have a shutter so I may be wrong). You may need a special adapter made. KFry

[rguinter]

It is called Magic Goerz size. Proprietary. The size you measured is probably it. They used some goofy size not intended for filters. That is what the slot in the side of the barrel is for (but you have a shutter so I may be wrong). You may need a special adapter made. KFry

Thanks Kirk. Much appreciated. My aging eyes are not so good at reading the calipers these days. And the in-between measurement had me wondering.

If the original barrels had slots then I suppose they were putting filters at a focal plane somewhere between elements.

If the thread size is proprietary as you suggest that will add some difficulty to my task for sure.

Thanks again. Bob G.

[Steve Hamley]

They didn't use screw-in filters because they were designed about a century before screw-in filters. They used push-on series filter adapters.

http://silverbased.org/series-filters/

Cheers, Steve

[Steve Hamley]

Also see:

http://www.largeformatphotography.in...ar+filter+size

http://www.largeformatphotography.in...ar+filter+size

http://www.largeformatphotography.in...ar+filter+size

http://www.largeformatphotography.in...ar+filter+size

Cheers, Steve

[rguinter]

They didn't use screw-in filters because they were designed about a century before screw-in filters. They used push-on series filter adapters.

http://silverbased.org/series-filters/

Cheers, Steve

Thanks for the link Steve. Yes I thought of trying to find some kind of adapater that would just slip on the OD of the lens. Which looks to be about 51.6 mm. Actually in the past I recall using black tape to hold 52-mm filters in place which slide on nicely in reverse.

It's a very old lens that I've only used a few times. But it is a great performer and I'm thinking would do well with infrared film.

Bob G.