View Full Version : Filter thread/Cokin P?

20-Mar-2002, 10:01
I have a Schneider Angulon 90mmF6.8 with a filter thread size of 40.5mm. I use t he Cokin P filter system and cannot find an adaptor ring for this size, any sugg estions?.

paul owen
20-Mar-2002, 10:50
I'm 90% sure that Cokin make a 40.5mm as I had one for a 100mm Apo Symmar. If not try a step up ring.

Noshir Patel
20-Mar-2002, 10:52
Step up ring to a size for which there is an adapter ring? (If you can't find a step up ring, then you would seem to have a real problem...)

Per Volquartz
20-Mar-2002, 13:11
If you use a screw-in type filter on a 90mm lens you may get corner cut off on extreme displacement / shifts. Use a bellows type lens hood that accepts filters.

20-Mar-2002, 14:34
If a screw-in filter is going to cause problems with cut-off, then a bellows-filter holder will only be worse - much worse!

Per Volquartz
20-Mar-2002, 15:23
A bellows lens hood / filter holder should be attached OUTSIDE the lens, NOT screwed into the lens thread! (The lens shade / filter holder should be clamped on the lens on the outside...) The best system is what SINAR uses: an extra bellows as a lens shade, with the ability to dial in flat "blinds" to minimize flare and get maximum contrast.

The way to check if you get cut off with a lens shade is to look through the camera, from the front, at the working aperture, with the shutter open, Look at each corner of the ground glass (from the front of the camera). If you can see each corner clearly there is no cut off. Dont try to look at the groundglass from the rear to check for cut off - the ground glass will fool you.

Colin Carron
20-Mar-2002, 15:45

The Cokin A range has a 40.5mm adaptor ring and works with the Angulon 90/6.8 without vignetting.

Massimo Squillace
21-Mar-2002, 08:09
Cokin doesn't sell a 40.5mm adapter for the P holders.

I had a similar problem some time ago and resorted to use a step-up ring (by the way, the best quality step-up rings IMHO are those by Heliopan - and they cover all your possible needs).

You may risk vignetting ... another option would be to have an adapter custom made for you.

Brian Ellis
21-Mar-2002, 08:58
I had the same problem when looking for a 40.5 adapter ring. I couldn't find one and ended up having one made by Steve Grimes.

janez pelko
22-Mar-2002, 08:42
I had the same problem and I just bought 40.5-52 stepping ring, I think from Kaiser, Germany. It is not quite top quality, but I never had any problems unscrewing it. And Cokin makes P ring for 52mm diameter. Best regards, www.janez-pelko.com

William Lindley
26-Mar-2002, 21:04
Hi Lee, I had the same problem. It was solved by the wonderful folks at Calumet, San Francisco. They sold me a 40.5 to 49mm step up ring from Tiffin and a 49mm Cokin P HOLDER, which also fits another lens in my bag. I belive the ring was less than $20.00 and works very well.

good shooting, Bill