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wjmva
29-Nov-2010, 13:48
Does anyone have a 203mm Ektar f7.7 lens with front filter threads?

Mine looks like 37-38mm and I want to step up to 67mm filter size which my other lenses use. None of my filters or adapters fit and my local camera store closed down.

I also need a Technika type lens board drilled to fit the 39mm diameter threads on the back of the lens.
Thanks

Mark Sampson
29-Nov-2010, 15:23
These Ektars were meant to take threaded filters; they used a press-on filter ring that took Series filters. These filters were unthreaded and were held in place by a retaining ring. There were many such adapters; each one had its own number and were labeled, for example, "Kodak Filter Adapter #48, 1-5/8" to Series 6". Each lens had its own adapter, so there were dozens of different ones. A complicated setup, but it let you use one set of filters, and it pre-dates the mm-sized filter system that came in with Japanese 35mm cameras. (Nikon's idea to make most of their lenses for the F take 52mm filters was a radical idea in the '60s.) If you search on the front page of this site you may find out which adapter fits your lens; if not perhaps someone will chime in with the web address of the site that's full of Kodak lens data; I forgot to bookmark it. Once you have that ring, with luck you can find an (uncommon) Series-to-mm filter adapter ring. Then you'll be in the modern system and you'll be good to go. I had those two adapters on my 203/7.7, but they went when I sold the lens...

John Koehrer
29-Nov-2010, 16:34
If you measure the outside of the lens, that will give you the diameter of the adapter.
That was step one. You need to get to a Series Vlll ring.
Usually if you're in the area of 40mm it's going to be a Series Vl a little more unusual is Vll. I don't recall ever seeing a 40mm-Series Vlll but that doesn't mean they don't exist. There's no real problem doing this, just stacking the rings.
The best part though is the Series Vlll is a 67mm female thread, so you don't need a retaining ring. Yay!

Robert A. Zeichner
29-Nov-2010, 17:47
Does anyone have a 203mm Ektar f7.7 lens with front filter threads?

Mine looks like 37-38mm and I want to step up to 67mm filter size which my other lenses use. None of my filters or adapters fit and my local camera store closed down.

I also need a Technika type lens board drilled to fit the 39mm diameter threads on the back of the lens.
Thanks

203 Ektars were mounted in both Kodak Supermatic shutters as well as Graphic (Synchro Compurs). I own both. My guess is that yours is the latter as that one takes a 38mm slip on series 6 adapter ring. The ones mounted in Supermatics take 33mm slip on adapters. As far as adapting your lens to 67mm, I would advise against this from personal experience. You would need to go from series 6 to series 8 (67mm) which might necessitate a series 6 to 7 adapter in between. By the time you hang all this stuff on a 38mm diameter lens and then add a filter, you will have so much weight, it would fall off and that's with no lens hood (which you should always use). It's happened to me. I would suggest a series 6 to 7 step up ring and then to modify that ring to take 52mm (very common) filters. I've done this and it works quite well. I have a supply of series slip-on adapters and might also have a 6 to 7 step up adapter as well. PM me if you are interested and I will give you a price.

Doremus Scudder
30-Nov-2010, 05:19
Kodak recommended a 33mm or 38mm to Series VI push-on adapter (as Robert noted above). You may be able to find an old one somewhere, and you can certainly get one made by S.K. Grimes or other photo machinist. If the latter, you can have it made to take regular size filters.

I machined the Series VI adapter that came with my lens to accept a step-up ring and use 52mm filters with it now. I would also agree that 67mm is a bit too large for the lens.

Hope this helps,

Doremus Scudder

John Koehrer
30-Nov-2010, 12:26
Most of the additional weight will be in the 67mm filter itself.The rings have negligible weight. The other consideration would be whether the 67mm filter inhibits operating the shutter.

gnuyork
30-Nov-2010, 20:44
I have that lens mounted in a compur. Not sure of the thread size, but when I bought it (used), it came with a screw on filter holder and a lens hood.

Sorry that's probably no help.

bigeye
19-Dec-2010, 18:10
The '47 203mm Ektar (Supermatic shutter) I have came with the "Kodak 1 5/16" (33mm) Series VI Filter Adapter" and a bunch of nice old Tiffen Series VI filters. You can easily find the adapters on ebay and elsewhere.

I have a variation on the OP's question; What are threads of the *retaining ring* of the 1 5/16" Kodak adapter?

I'd like to see if you can use a screw-in filter in place of the retaining ring and Series VI filter. Hoping to get lucky and find that they are a form of filter thread.

***Later Edit***

On further research it's more complicated... The new question is whether someone can confirm that a 44mm step-up ring (to 52mm in the Heliopan adapter's case) will screw into the Kodak retaining ring threads?

Thanks in advance.

- Charlie