Sensitizing Film for Infrared Photography

[Too Many Cameras]

A while back I found a formula in a 1934 book on infrared photography to sensitize over-the-counter plates (Agfa, Ilford, and others) to infrared spectra. The plates did not come with infrared sensitivity. So my question is does anyone know if this will work with modern film emulsions? Here, for reference, is the formula:

For Cryptocyanine (Kryptocyanine)
1 part in 10,000 solution of methyl alcohol (1cc)
Industrial spirit [ethanol, I think] (165cc)
Distilled water to make 500cc.

Bathe plates for 3 minutes in the solution
Dry in a current of cold air

I found the ingredients at Sigma-Alrdich (http://www.sigmaaldrich.com/catalog/...g=en&region=US) for a reasonable cost, but cryptocyanine is not a chemical that I'd be comfortable storing in my apartment, so I've not yet gotten any because the smallest size is 250mg, enough to last me a lifetime of sensitizing film.

Users here seem pretty up on the scientific side of this, so I thought this might be a good forum to ask about this.

David

[Light Guru]

Why not just buy infrared film?

[Frank Pittel]

I can't imagine how soaking any modern film in a liquid would be anything but bad. Seems like sheet film in hangers would be best but getting the film flat after it dries would be a trick!

[Brian C. Miller]

You should ask this over on APUG. There are at least two ex-Kodak engineers there, and some very active chemists.

The first thing that comes to mind is that the antihalation layer would come off. Good or bad, depends on the result. The Kodak IR film didn't have an antihalation layer. Otherwise, I don't think that 250mg (1/4 gram) would be more dangerous than other household chemicals. If you are worried about it, keep it in a box of charcoal to absorb any potential fume leakage.

[Too Many Cameras]

Thank you, guys! I should probably sign up at APUG. I was thinking I would try this on Lucky brand 4X5 film since it already lacks the AH layer, and is cheap, and the box I got was free.

On my way to sign up at and start reading posts at APUG.

[Andrew O'Neill]

I thought about doing this with xray film... but then I saw the price of the dye. I read somewhere that it can work. Pretty expensive experiment, though.

[WayneStevenson]

I'm usually pretty casual with chemicals and their exxagerated warnings. But that stuff is pretty serious according to the MSDS. They recommend a trip to the doctor's / hospital with just skin contact.

Are you sure you want to be handling this in liquid form in the dark???

Would you be able to safely handle the film after coating?

Where would you go about disposing your used solutions? These aren't paints and solvents. You can't take highly toxic wastes to your area landfill or chemical collection. And you definately cannot pour this stuff down your drain.

[WayneStevenson]

Have you looked through their list of IR dyes for something a little less toxic? Maybe futile, but worth looking.

http://www.sigmaaldrich.com/material...lePage=9540639

[Too Many Cameras]

Yeah, the MSDS is serious. One of the environmental engineers at work suggested it's toxic, but not the worst thing ever (the long-term concentration isn't so bad and most of the acute toxicity is based on ingestion.) As for disposal, yeah, that's an issue, but so is proper disposal of any film fixer. Fixer can't legally go down a drain or be landfilled in the U.S. because of the silver halide that can contaminate groundwater for a few centuries. So my solution for disposal would be to get rid of it during a household hazardous waste collection day.