Searching for filter sizes - Red Dot, Velostigmat

[gevalia]

I have 3 lenses that I am trying to find filter rings for. I've been unable to after searching for a while so I hope you all can help.

1. Goerz Red Dot Artar 14" f9 - appears to be a course thread. It looks to be somewhere around 52mm.

2. Goerz Red Dot Artar 9 1/2" f9 - fine thread. It looks to be somewheee around 40mm.

3. Wollensak Velostigmat Series II 7 1/4 f4.5 - fine grain.

Thanks for your help.

I wonder if this is the kind of thing we need a sticky for.

[Steve Hamley]

They don't use standard screw-in filter sizes, they use push-on Series filters/adapters/accessories. This question gets asked several times a year, so a stick thread for commonly asked questions may be useful.

Cheers,

Steve

[gevalia]

Steve,

Forgive my ignorance. Push on? Does that mean they push on the outside of the front cell?

[Steve Hamley]

Absolutely nothing to forgive sir, it's the logical question.

Yes, the outside of the front cells were standard sizes and the filter adapters had a friction fit. That's why many old lenses had enamel wear around the front cell. The threads just hold the retaining ring for the front glass and are not standard.

I'll try to post a jpeg soon.

Cheers, Steve

[mandoman7]

I've been recently addressing this same problem with 2 Goerz's, a 9 1/2 and 16 1/2. I did lot of googling and searching on this and other forums, and found some good suggestions.

The simplest method is to send the lens to SK Grimes and have an adapter made (at some cost!). But you won't get that investment back in resale most likely.

The best suggestion I found was to get a step-up ring whose inner diameter is just larger than the outside of the front element. You then use a wide rubber band (I used one from a broccoli bunch) as a fitting interface and slip the step-up ring on to the rubber which should fit snuggly. I tried this and it worked quite effectively. With the appropriate step rings on other filters, I've standardized all 5 of my 4x5 and 3 of my 8x10 lenses to a 67mm size and only need to carry one set of filters in that size.

Now having had a few shoots in the field, I gotta say it really helps with keeping track of filters and lens caps. I'm glad I went to the effort.

JY

[Jan Pedersen]

Gevalia, If you like your lenses and intend to keep them, have SK Grimes make you some adaptor rings. They are a little pricy but very nice. For the artars you may not even need to send them your lenses, they do have many common lens data already.

[Nathan Potter]

Gevalia, The friction fit adapters Steve mentions are a crude solution to filter holders. The ones I use are a collection of old Kodak Series sizes with different Inside Diameters (ID). What grabs the Outside Diameter (OD) of the lens is a series of slots cut into the contact ring. The slots in the ring are slightly springy so that each tooth, so to speak, will apply a bit of inward radial force to grip the OD of the lens. There are usually a few dozen slots around the perimeter of the adapter. The springiness is limited so the inward force can be strong and that is what wrecks the paint job on older lenses. The rubber band trick as mentioned can be used to minimize the damage. I use polyimide tape around the rim of good lenses to avoid damage. There may be more modern version of these "objects of disrespect" that have standard filter threads, I don't know.

Nate Potter, Austin TX.

[Jim Rhoades]

In my studio tool cabinet I have a drawer full of old cheap filters, adapters and other odds and ends. When I find a lens that I want a standard filter ring for, I start digging. A old Wollensak triple 12,20,25 is just a touch under 62mm. I file down the threads of a filter so it will just slip in. Then remove the split ring and glass. A bit of household "Goop" around the edge area and the next day you have a filter ring that will never come off by accident. You can however pull the ring off with pliers and rub off the Goop without any damage to the lens.

This is not a fix that a lens snob would try, but then they would not be using a 70 year old triple anyway.

[gevalia]

Jim, Jan, JY, Steve - thanks a lot. A little kick in the right direction is all I need. I'm an engineer, I should have been thinking like one.

[Steve Hamley]

Hey Gevalia, I'm an engineer too, but that won't help us. We're talkin' Kodak and his brothers here!

Cheers, Steve

[gevalia]

Success -

Well, I've been able to make the filter rings I need. Thanks to JY and Jim for the suggestions.

I had a bunch of rings in different sizes already from my MF and digital lenses (mostly Cokin and Lee). I found that a 52mm ring is 3-4mm to large for the OD of the Goerz 9 1/2 lens I chose 1st. I had some 2mm thick cork sheets laying around from when I made some header gaskets a while ago. AutoZone - a few bucks. Anyway, I crazy glued a piece around the inside of the ring, let it dry, then glued another inside that one. When it dried I shaved th excess with an Xacto and it fits "perfectly" around the outside of the lens. The cork will not mare the finish and it stays on and also comes off easy.

Tested all day today, works like a charm.

No reason to spend $60.