Ektar Filter thread Sizes?

[laverdure]

Ektar LF lenses thread sizes... my research indicates they're weird. Some people say they were designed with imperial rather than metric thread sizes... some people say they need special "series" adapters... people say a lot of things. Many say "go talk to S.K. Grimes." But that's a more expensive solution than appeals to me just now.

I just want to be able to use 49mm filters on my 100mm WF Ektar.

Measuring the WFs threads, it looks like it might take a 40mm. But I might be half a mm off, or it might be imperial... So, rather than buying three step-up rings and maybe finding that none of them fit, I figured I'd ask this question here, to see if anyone can help.

Any suggestions?

 

[David A. Goldfarb]

40.5 mm isn't an unusual size, but most of the Ektars I've seen take series sizes.

If you own a lot of odd sized lenses, you might get a clip-on filter holder (I have one with barn doors made by Voss that I found second hand at KEH). There are a few different types like the Lee Gel-Snap, which uses a rubber band, and another one that has four springs that Calumet sells.

 

[Neanderman]

The 100 mm WF Ektar was designed to use Series VII filters with a special adapter ring. Unfortunately, the special adapter ring (and the adapter ring insert) for that lens came supplied with the lens. Which means, if you didn't get one with the lens, finding one could be a challenge.

I have little doubt that SK Grimes could fabricate a custom step up ring to what ever filter size you want, but I doubt it will be cheap.

Ed

 

[Keith Pitman]

I have two WF Ektars. The front thread of the 190 WF Ektar will take 67mm filters directly. I cannot determine what the front thread of the 250 WF Ektar is; it appears to be about 87mm. If someone knows for sure, please let me know. I believe it originally had a series filter retaining ring, which was not with the lens when I acquired it. For anyone doing research, there is a lot of information on Ektar lenses in an old Kodak publication titled, "Camera Technique for Professional Photographers." Someone had posted scans of this on the internet a few years ago, but I no longer have the address. There is a good amount of information here, also:

Dead Link Removed

 

[David A. Goldfarb]

The 10" WF Ektar is Ser. IX, I'm fairly sure. I have an adapter for 4" square filters that I use on it.

 

[Neanderman]

I cannot determine what the front thread of the 250 WF Ektar is; it appears to be about 87mm. If someone knows for sure, please let me know. I believe it originally had a series filter retaining ring, which was not with the lens when I acquired it.

The 250mm WF was another that came with a special adapter ring. And it was designed for Series IX.

I don't have any more detailed thread info on these. I wish.

Ed

 

[tchamber]

I just want to be able to use 49mm filters on my 100mm WF Ektar.

39.5mm screw-in.

Best bet would be to get a 39.5mm Series VI ring, then get a step up from the Series VI (44mm) to a standard size, e.g., 49mm.

 

[MarkS]

The WF Ektar lenses were meant to take unthreaded Series filters, held in by a retaining ring that came with the lens (which are often gone now). Long ago I searched and found a (Series 7 to 52mm) adapter, which lives on my 135mm WFE. Series-thread to mm- thread adapters were hard to find pre-internet, and not much easier to find now. It's usually the other way around, as if you'd want to use ancient uncoated Series filters on your modern lenses.
Other Ektar lenses were meant to use a press-fit adapter to take Series filters. Either way, it's time to search the junk drawers of old camera stores

 

[henrysamson]

I have two Ektar/Commercial Ektar large format lenses and I had SK Grimes make step up rings for the rear elements -> 72mm filters . . . or is it 77mm. Whatever, it is the same for each lens and I just keep the threaded step up ring on all the time and have one set of filters. For a WA Dagor I bought an old 72mm filter and took the glass out. Then epoxied it to the rear of the wood lensboard (the lens does not protrude past the rear face. Painted it all black and the same filters can be threaded to the old filter ring and it does not vignette. This has worked well for me. BTW, the step up rings are black anodized aluminum.

 

[laverdure]

39.5mm screw-in.

Best bet would be to get a 39.5mm Series VI ring, then get a step up from the Series VI (44mm) to a standard size, e.g., 49mm.

Thanks. This is my introduction to the Series system. Frankly it seems like a PITA.

So series-to-metric step-ups aren't common. There certainly aren't any VI-to-49mm step-ups I can find just now. If I put a search out, am I likely to find one within a few months?

If not, I'm thinking my best bet at the moment is to find some way to friction-fit a relatively common 39mm-49mm step up and call it a day.

 

[tchamber]

So series-to-metric step-ups aren't common. There certainly aren't any VI-to-49mm step-ups I can find just now.

The front-facing thread of a Series VI holder *should* be 44mm, if it's a Kodak. (The Series designation seems to have been a loose standard and non-Kodak holders may have non-conforming thread sizes.)

Check with Camera Depot, they sell all sorts of step-up and -down rings.

 

[Doug Webb]

I found series system push on filters for my 100mm WF Ektar and 203 Ektar on Ebay. The push on filter that fits the 100mm WF EKtar that I have is inscribed "Kodak Series VI Adapter Ring 1 21/32 in. 42mm. This is only good for the small series VI filters that fit into the holder or for mounting a lens hood with the same threads. If you wanted to epoxy a step up ring to the front of the adapter you could use standard metric thread filters. As far as I know all Kodak Adapter rings I have are not metric thread. I have never used my adapter, instead I wrapped a rubber band around the outside of the lens and pushed a step up ring over the rubber band for a snug fit, the threads on the step up ring arent used to mount the ring to the lens, they are on the outside. I did that because after looking at the adapter ring I was afraid it would vignette with a wide field lens. The step up ring had metric threads. Then I lost the step-up ring and epoxied another step up ring to a 42mm plastic lenscap that I had cut out so the the lens could "see through" the part that is supposed to protect the lens, leaving essentially a plastic band around the lens. I just looked for it and I can't find it so I can't tell you which size step up ring I used. All that said, I think you can find an easy work around. Good luck,
Doug Webb

 

[laverdure]

Hi Doug,

Thanks. You are a scholar and a gentleman. I fully intend to emulate the spirit of your example.

 

[tchamber]

I took a look at my setup (I have that lens):

39.5 Series VI screw-in adapter -> 44-52mm step-up ring

Just those two, very simple. Everything else (compendium, et al) hangs off the step-up ring.