Rollei Infrared 400

[tgtaylor]

I use the Cokin X-Pro series filter. It's listed as a X007 equivalent to an 89B Wratten. It comes either as a 170x130mm rectangle or 120mm circle. Either way it slides into a Cokin X-series holder. The trick is to make an adapter to fit the Cokin X-holder to your lens. I make my adaptors out of various diameter PVC drain pipe sections. That way I can use the same filter on my 40mm Distagon and my 360mm Rodenstock.
For smaller lens Cokin's P-series holder has threaded inserts for popular thread sizes. Then the filter is listed as a P-007.
The Cokins aren't actually as restrictive as an 89B. I figure my Rollei film to be 6 ISO with the 007, whereas it seems more like 3 ISO with an actual 89B Wratten.

I use the Cokin rectangular 100mm 007 filter with the Cokin Z-Pro holder with a 95mm filter ring and several step-up/down rings from 49mm to fit all of my 35, MF, and LF lenses. It's been a while since I last shot IR but IIRC 3 ISO was the exposure setting.

Thomas

[paulbarden]

One more question, it's been a long time since I've shot IR film: is re-focusing still a thing with this film?

Unlike Kodak HIE, this is not an issue with the Rollei film. Focus as normal and you're done.

[Ari]

Unlike Kodak HIE, this is not an issue with the Rollei film. Focus as normal and you're done.

Sweet! Thanks, Paul.

[Andrea Gazzoni]

a bit confused here about the ISO setting to use with the Cokin P007 filter, as almost all I've read says ISO 25 with this film.
I am ok with bracketing on roll film, but would like a starting point more in the ballpark

[abruzzi]

a bit confused here about the ISO setting to use with the Cokin P007 filter, as almost all I've read says ISO 25 with this film.
I am ok with bracketing on roll film, but would like a starting point more in the ballpark

Shooting it on 35mm (Kodak Retina IIIC) I did a roll with every shot at both 25 and 12, with a no-name Chinese R720 filter. Both seemed reasonably dense, but I found the 12 overall closter to where I like it. I haven't tried it at lower EI or on 4x5 though. The camera was recently CLA'd so I have every reason to expect the shutter speed was moderately accurate.

[tgtaylor]

Back when I was shooting IR the consensus was that the filter required 10 stops - that would put Rollei 400IR at ISO 3. But ISO 6 sounds familiar. What I would recommend is taking 4 test shots in the same light at ISO's 3, 6, 12, and 25 and see which one gives the result you are looking for.

Thomas

[Ari]

Some online research, and my own crude test, indicates that the filter takes about 6-6.5 stops off the reading.
So it is with my filter. Other 720nm filters may block more or less. It's a wild world out there.

[John Olsen]

a bit confused here about the ISO setting to use with the Cokin P007 filter, as almost all I've read says ISO 25 with this film.
I am ok with bracketing on roll film, but would like a starting point more in the ballpark

Well, it depends a lot on exactly which filter you use and the environment in which you shoot. Also, some of us have different metering habits. Try a test roll with bracketing and then you will know what setting work for your exposure and development process. BTW, I'm using HC-110 "B" for my work. ISO 25 seems pretty unlikely, though.

[grat]

Hoya R72 seems to be about 6 stops from my testing.

[Ari]

Using the new filter on expired (2007) Maco IR820c film while I wait for the Rollei film to arrive.