12" Goerz Apo Artar Red Dot filter size?

[Bernice Loui]

Skip the threaded filter idea for Goerz America and similar vintage lenses as the Goerz lenses were never designed to have filters threaded in. The front beauty ring does un-thread allowing a specific threaded adapter to be used as a filter holder. Originally APO artar is a process camera lens, these threads were intended for a 90 degree prism to be mounted to the front of the lens. This why the lend barrels are made of brass and SO robust as they are not intended to be used with a light weight field folder view camera where lowest weight is a primary concern.

As for filters, better way is to use a 4x4 or 100x100mm square filter set up with the filter holder mounted on the camera.. This is what evolved as a filter set up on the Linhof TK23s. It is a modified series 9 filter ring with a vintage Kodak 4x4 gel holder painted black on a cold shoe adapter made to do this. This set up is easy to use (threaded filters are a hassle to install/remove and must be sized to the lenses to be used), lens front thread independent, stable, versatile and easier to carry than a stack of threaded filters. This set up allows using series 9 filters or 4x4 _ 100x100mm filters.



~IMO, the thread on filter thing is a carry over from hand held portable camera habits, that does not transfer well to the needs of view camera ways.

Bernice

[senderoaburrido]

Unfortunately, the filters I want to use do not come in formats that will fit such a holder. If it's threaded, it has a pitch and a thread diameter. I can't get the specialty filters I use in broad squares. I will need to make an adapter.

[Bernice Loui]

Curious, what specific types of filters are these that are not available in 4x4" or 100mm square?

Bernice

Unfortunately, the filters I want to use do not come in formats that will fit such a holder. If it's threaded, it has a pitch and a thread diameter. I can't get the specialty filters I use in broad squares. I will need to make an adapter.

[senderoaburrido]

The B+W 403, and the Baader U. Although I do think the Baader U might come in a 2" square, I seem to recall seeing that. That's a future purchase, however. Right now I only have the 403's, and they are no longer in production, so I am stuck with the circular ones I've got.

[Bernice Loui]

Both appear to be UV pass filters, specialized.. Still using a non lens mounted filter holder remains an option.

This is the same 4x4" _ 100x100mm filter holder. This holder can accommodate those square filters or series nine or 77mm threaded. Using step-up/down rings most any threaded filter can be used up to 77mm.






Bits of this filter holder. It is patterned from the Sinar filter holder using a Tiffen Series nine to 77mm filter holder. Made adapters to fit the Linhof TK23s cold shoe and other related bits. The 4x4" _ 100x100mm filter holder is a Kodak gel holder for series nine. Camera mounted filter system negates the need for knowing lens front thread size in every way. Long as the filter in holder is larger than the lens front element and can shade between the lens front to filter, its good. Gave up using threaded filters on a view camera decades ago due to the non-standard sizing of vintage lenses.. It was simply too many variations to deal with.




Giving up the goal of threading the filter to the lens allows many options that simply work better overall as a filter system. The non-round filter system is pretty much the standard for cinema and video, they gave up the thread on filter deal long ago as the non round drop in is easier and more versatile in every way.

As for the Bader 2x2", adapting a filter holder works, even using rubber bands to hold the filter to a ring works..

Other optical filter suppliers:
https://www.edmundoptics.com/c/optic...EaAmV4EALw_wcB

https://www.omegafilters.com/product-types/uv-filters

and a long list of others via the web.


Bernice

The B+W 403, and the Baader U. Although I do think the Baader U might come in a 2" square, I seem to recall seeing that. That's a future purchase, however. Right now I only have the 403's, and they are no longer in production, so I am stuck with the circular ones I've got.

[Joseph Kashi]

Unfortunately, the filters I want to use do not come in formats that will fit such a holder. If it's threaded, it has a pitch and a thread diameter. I can't get the specialty filters I use in broad squares. I will need to make an adapter.

Here's a simple and effective way to use standard glass filters on Artars, Dagors, and Ektars, etc.

https://www.largeformatphotography.i...highlight=Voss