Filter to make IR Flash

[bvy]

I'm intersted in trying infrared flash photography. I want to use my Olympus XA2 or XA4 and A16 flash, and go out shooting in public at night. What sort of filter can I put over the flash? I read a blog post recently that suggested that I can use an Ilford SFX A filter. They were cheap, but Amazon has long since sold out of them, and I can't find them elsewhere.

So I'm looking for some other inexpensive alternatives -- improvised ones if necessary. What kind of filter can I put over the flash? For lack of anything better, someone suggested that black trash bag material would work and even black electrical tape. Will it really?

Thanks...

[ntenny]

I'm looking into the same thing. So far I've found that Freestyle has gel filters equivalent to Wratten 87 and 87c for quite reasonable prices (US$26.99 for 4x4 inches). A gel 89b is available from Kodak (B&H has them, for instance) but it's expensive, north of US$60 for 3x3 and US$100 for 4x4.

I can't figure out whether the SFX filter is equivalent to 89b or not.

-NT

[Pinholemaster]

Very simple solution. You need to tape a polyester Wratten or Lee Infrared filter over your strobes lens.

3 inch: http://www.bhphotovideo.com/c/produc..._Infrared.html

4 inch: http://www.bhphotovideo.com/c/produc...ra_Red_87.html

Your Infrared film should see the IR strobe, but make sure you do testes before an important shoots.

[ntenny]

Not to follow up to myself, but I did a little more poking around and found this promising article:
http://amasci.com/amateur/irgoggl.html

The author apparently has combined multiple layers of "Congo Blue" and "Primary Red" visible-light filters to get something that's visually opaque but passes IR from about 720 nm---basically the equivalent of an 89b. I'm going to have to try this.

-NT

[2F/2F]

I am afraid that if you filtered the little flash on an XA, you'd have almost no light hitting your subject. I would suggest something that has more power.

[mopar_guy]

I think that you are about 40 years too late with this idea. Just get out your Speed Graphic and your Graflite and use some GE #5R flashbulbs with your infrared film.

[Photo Engineer]

Yes, the flash must have IR output at an amount useful to you. After all, most flash units were designed to have maximum output in the visible range.

There is some IR output from standard flash units. You can feel the heat on some. If you cannot feel heat when you test flash your strobe, then there is probably little or no IR output.

PE

[ntenny]

I am afraid that if you filtered the little flash on an XA, you'd have almost no light hitting your subject. I would suggest something that has more power.

It's been done successfully before:
http://www.kpraslowicz.com/2009/11/2...n-olympus-xa2/

I do intend to try it with a higher-output flash, though.

-NT

[blade_o]

you can use blank (developed but unexposed) E6 film. 35mm if you have a small flash, or 120 if your flash is larger. Just take and attach two strips of either to the front of your flash and there you go IR filter. IDK about the actual spectral emission of using E6, but it has always worked good for a buddy of mine.

[Andy K]

I think using a flash with IR would be a waste of good IR film. Unless you want specific skin tones I see no reason to do this. Also at night you won't get the full IR 'effect' because there is no sunlight. You would be better off using an ordinary bw film, and saving the IR for daylight subjects. (IMO).