Infrared: fogging + film discontinued ?

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I am currently experimenting with Kodak Infrared film and a 4x5. I have used HIE before in 35mm with great results. I am having a problem with 4x5 always coming out fogged. There is absolutely nothing on the film but a foggy exposure. I am using the same darkroom and chemicals as before. I am currently using an ebony camera and jobo film tank. Does anyone have an answer?

Also: I have heard that kodak is discontinuing their Infrared 4x5. Is this true? Does Macophot the same product?

Thanks, Ken

-- Ken (photo@osbornephoto.com), December 07, 2000

Answers

Response to Infrared??????????

Perhaps the bellows of your camera are not opaque to IR. Two experiments to try: first, make a fake exposure, doing everything except removing the dark slide. This will test for fogging exposure anywhere in your procedure except during the moment of exposure. Second, try wrapping the bellows in aluminium foil and see if the amount of fogging is reduced.

Yes, Kodak has cancelled 4x5 IR film. Macophot is now making a 4x5 IR film, which differs in some ways from the Kodak product.

-- Michael Briggs (michaelbriggs@earthlink.net), December 08, 2000.


Response to Infrared??????????

I had a similar problem with HIE. Turned out my camera (an old Calumet) was not opaque to IR. At $2 a sheet I was not impressed.

I tested my film holders and found them to be pretty IR-proof. I didn't attempt to use my JOBO tank with it, and that might be a problem also. Perhaps you could email Ebony and query them about their cameras' IR lightproofing?

-- John O'Connell (boywonderiloveyou@hotmail.com), December 08, 2000.


Slightly off point here, but Central Camera in Chicago indicates that it has some Kodak Infrared 4x5 sheet film.

-- Donald Brewster (dpbrewster@prodigy.net), December 09, 2000.

Greetings,

The problem you are experiencing may be caused by your bellows. Not all bellows are IR proof. As long as your film is "fresh," that is not fogged from the box and you're loading in a truly dark room, you should be OK. I use a JOBO drum with IR and it is IR light tight. You could test your bellows and film holders. Process a sheet that has just been in the holder (no exposure) one that is in the camera with dark slide removed and shutter closed and one straight from the box. If you get different levels of fog on these unexposed sheets you should be able to pinpoint the culprit, but I'd suspect the bellows.

Kodak states that they will discontinue HIE in 4x5 at the end of this year. MACO does make 4x5 IR film, but I don't know who carries it, or how well it works. I just shot my first roll of MACO 120 earlier today but haven't processed it yet.

Regards,

-- Pete Caluori (pcaluori@hotmail.com), December 10, 2000.


There are a lot of possibilities. As others have mentioned, your camera bellows may not be safe for IR or, alternatively, it could have some tiny pin hole leaks that haven't affected normal film but that are fogging your IR film. At the prices Ebony charges I would hope their bellows is safe for IR but some otherwise excellent cameras have bellows that are not (e.g. Wisner) so maybe that's the case with Ebony.

Since you're processing your own film, I'd take a real hard look at exactly how dark your darkroom is. Light leaks that are insignificant with normal film will fog IR film. I remove my watch with glowing numbers when loading and unloading IR and I also cover those glow in the dark pieces of tape that I have on my enlarger. If you have any of those, cover them up. Does your timer have glowing numerals? If so, cover it up. These kind of things don't affect normal film but they can definitely affect IR. 100% darkness means 100% darkness with infrared. I'dsuggest that you turn off all the lights in your darkroom and sitthere for 10 minutes. Then start looking around very carefully.

The other possibilities are your film holders and your tank. I use modern Fidelity Elite plastic holders and they are IR safe. I also develop in the BTZS tubes and they are IR safe but conceivably the Jobo is not.

Personally, I think the most likely culprit is some very minor light coming from somewhere in your darkroom but that's just a guess.

-- Brian Ellis (bellis60@earthlink.net), December 12, 2000.



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