question for indoor IR lighting

[andatron83]

I have been working with hie film for a few months now and have shot it exclusively outdoors. I was wondering if anyone could give me some advice on where I might find something I could use as a filter on a halogen work light for IR photography indoors. I was wanting to replicate some of the medical IR applications and also if anyone knows at what frequency range this can be accomplished at (from my limited understanding of opaque filters). Thanks for your time.

 

[KMac]

You can use two layers of unexposed but processed slide film as an IR filter (ie. passes IR but blocks visible light). The cheapest way to get this material is to buy a roll of 120 E6 film (any will do) then get it processed. If you are using this over a halogen light that will be permanently on, temperature may become an issue. You may need to experiment with how far you place it from the light source.

I have never used this material for the exact purpose you have suggested but I have used it over a flash head and also to improvise an IR filter for my video camera so that I can preview scenes I wish to photograph with HIE. I dont know the exact cutoff of this filter but judging from how little I can see through it (ie. only very bright red lights) it must be right at the very limit of the visible spectrum.

I hope this helps,
Kevin

 

[andatron83]

That seems like a fairly reasonable solution. I've been looking for some red covers for the halogens but haven't found what I'm looking for but the slide film with a box built to focus it might be very possible. Thanks for the advice.

 

[Garbz]

I have seen this used on flashes. Just be careful that you don't melt it with a continuous light.