# Best materials make softbox to diffuse 850nm IR



## -Photographer- (Sep 27, 2015)

I want to make an 850nm ir softbox diffuser, what would be the best materials to use? Since ir goes through materials more than visible light.

It will be stationary so I don't mind of the materials are heavier than those used in standard softboxes.


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## JustJazzie (Sep 27, 2015)

Rip stop nylon is what I usually see suggested....

My "softbox" is diffused through a plastic-y shower curtain I had laying around. I'm pretty fond of the light it puts out!


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## petrochemist (Sep 27, 2015)

-Photographer- said:


> I want to make an 850nm ir softbox diffuser, what would be the best materials to use? Since ir goes through materials more than visible light.
> 
> It will be stationary so I don't mind of the materials are heavier than those used in standard softboxes.


Materials are generally not as transparent to NIR as some of the news reports would have you believe. I've taken loads of crowd scenes in IR & have rarely if ever seen any conclusive transparency issues. I have frequently seen visually black fabrics becoming quite reflective in IR which can easily be confused with IR skin tones...
I know some man-made fabrics are  translucent/transparent, so it might be best to just choose a light cotton fabric, or try a standard soft box & add a layer of cotton if more diffusion is needed.


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## KmH (Sep 27, 2015)

Humans can't see 850 nm IR light.
The OP's need is pretty specialized and I have no idea what material(s) would work.


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## JustJazzie (Sep 27, 2015)

KmH said:


> Humans can't see 850 nm IR light.
> The OP's need is pretty specialized and I have no idea what material(s) would work.


I can see by your response I must have misunderstood the original question!


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## petrochemist (Sep 27, 2015)

KmH said:


> Humans can't see 850 nm IR light.
> The OP's need is pretty specialized and I have no idea what material(s) would work.


Not anywhere near as specialized as you might think. IR photography is becoming relatively commonplace. At least 10% of the members of our local photo workshop have tried IR photography before joining. Two of us regularly use converted cameras, and several others are considering getting a conversion done.
Although I don't have a softbox I believe they are also relatively well known among photography enthusiasts.


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## -Photographer- (Sep 27, 2015)

Thanks, I just wanted to know what material would be best to diffuse the ir as much as possible.

So I would have lots of 5mm ir leds behind and I would like it to turn a series of spot sources into a fairly even large rectangle emitter that glows in nir.

Has anyone tested common materials viewing in the nir range?


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## petrochemist (Sep 28, 2015)

I've just had a reply from someone who regularly shoots IR with modifiers. He's never had any issues with just the standard kit. See here


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## -Photographer- (Sep 29, 2015)

Ok sounds good, do you know if it was still a bit spotty or even?


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## f2bthere (Oct 3, 2015)

There is a simple way to test this. Put your light behind the material in question, pointed straight at your lens on your IR sensitive camera. Take a picture. Adjust till you get a middle gray exposure of the material and it should be pretty obvious if you are getting relatively even diffusion of your light source or not. 

If you take your light source with you to a fabric store, you could even test before you buy.


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## -Photographer- (Oct 3, 2015)

Thanks, that's what I've been doing, but before I buy materials to test I was just wondering what other people found best.


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