Reflector for infrared photography?

We have a digital camera that takes IR photos of animals at night when
they come by and trigger a sensor. The camera is IR sensitive and we
have a separate IR light that lights up the scene. We'd like to
improve the lighting by bouncing the IR light off a reflector, instead
of directly lighting the subject. Do visible-light reflectors sold in
camera shops reflect IR light? If not, what does?

Thanks.

I have not tried it, but the silver ones should.

"jbk" <johnbkim@gmail.com> wrote in message
news:3cd2a213-0d85-41d0-9aa7-c2bbeb69d20a@s8g2000prg.googlegroups.com...
> We have a digital camera that takes IR photos of animals at night when
> they come by and trigger a sensor. The camera is IR sensitive and we
> have a separate IR light that lights up the scene. We'd like to
> improve the lighting by bouncing the IR light off a reflector, instead
> of directly lighting the subject. Do visible-light reflectors sold in
> camera shops reflect IR light? If not, what does?
>
> Thanks.


--
Joseph Meehan

Dia 's Muire duit

Joseph Meehan wrote:
> I have not tried it, but the silver ones should.

What is called infrared in photography is known as near
infrared in spectroscopy. The radiation in the near infrared
range is much more penetrating than visible light or
infrared of longer wavelengths. A thin coating of silver on
fabric may not work well.

>
> "jbk" <johnbkim@gmail.com> wrote in message
> news:3cd2a213-0d85-41d0-9aa7-c2bbeb69d20a@s8g2000prg.googlegroups.com...
>> We have a digital camera that takes IR photos of animals at night when
>> they come by and trigger a sensor. The camera is IR sensitive and we
>> have a separate IR light that lights up the scene. We'd like to
>> improve the lighting by bouncing the IR light off a reflector, instead
>> of directly lighting the subject. Do visible-light reflectors sold in
>> camera shops reflect IR light? If not, what does?
>>
>> Thanks.
>
>

jbk wrote:
> We have a digital camera that takes IR photos of animals at night when
> they come by and trigger a sensor. The camera is IR sensitive and we
> have a separate IR light that lights up the scene. We'd like to
> improve the lighting by bouncing the IR light off a reflector, instead
> of directly lighting the subject. Do visible-light reflectors sold in
> camera shops reflect IR light? If not, what does?
>
> Thanks.

You could try baking foil. That should pretty effectively reflect IR.
If you crumple it up and spread it out you should also get a pretty
evenly diffused 'light' off it. You might even be able to paint the
surface dark so as not to spook the animals with a big shiny thing.
Cheap to try out, so give it a go.

I am just speculating about how effective this will be but it should work.

jon

In rec.photo.digital ZenDiver <spicedhamme@yahoo.com> wrote:
> jbk wrote:

>> We have a digital camera that takes IR photos of animals at night when
>> they come by and trigger a sensor. The camera is IR sensitive and we
>> have a separate IR light that lights up the scene. We'd like to
>> improve the lighting by bouncing the IR light off a reflector, instead
>> of directly lighting the subject. Do visible-light reflectors sold in
>> camera shops reflect IR light? If not, what does?
>>
>> Thanks.

> You could try baking foil. That should pretty effectively reflect IR.
> If you crumple it up and spread it out you should also get a pretty
> evenly diffused 'light' off it. You might even be able to paint the
> surface dark so as not to spook the animals with a big shiny thing.
> Cheap to try out, so give it a go.

> I am just speculating about how effective this will be but it should work.

Look at the various materials through the live view of the IR camera,
or if it doesn't have live view, snap and chimp. That will tell you
how reflective they are.

--
Chris Malcolm cam@infirmatics.ed.ac.uk DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
[http://www.dai.ed.ac.uk/homes/cam/]

"ZenDiver" <spicedhamme@yahoo.com> wrote in message
news:fti3uv$9kc$1@registered.motzarella.org...
> jbk wrote:
> You could try baking foil. That should pretty effectively reflect IR. If
> you crumple it up and spread it out you should also get a pretty evenly
> diffused 'light' off it.

I must admit that I was intrigued by your question, and even though I shoot
almost entirely digital IR, I've never experimented with reflectors, since
most of my stuff is shot during the daylight hours. So last night I made
two reflectors, one with smooth aluminum foil, and one with crumpled foil.
The smooth foil reflector worked great. The crumpled foil appeared to
diffuse the light slightly, but did not reflect as much of the light onto my
subject. So yes, aluminum foil works great. Hope this helps.

-- Theo Benson, Grizzly Glen Photography

On Apr 8, 1:56 pm, jbk <johnb...@gmail.com> wrote:
> We have a digital camera that takes IR photos of animals at night when
> they come by and trigger a sensor. The camera is IR sensitive and we
> have a separate IR light that lights up the scene. We'd like to
> improve the lighting by bouncing the IR light off a reflector, instead
> of directly lighting the subject. Do visible-light reflectors sold in
> camera shops reflect IR light? If not, what does?
>
> Thanks.

Some do, some don't. Most metals oxidize rapidly with a clear/
transparent oxide coating. If that gets thick enough it can reduce
the reflectivity of the metal a bit in even the near IR where the
cameras work. Usually, however, the tarnish needs to get quite thick
to reduce near IR reflectivity so if it looks untarnished and shiny,
it will probably be okay. To be absolutely okay, professional IR
folks use gold plated reflectors, but this is overkill for the
occasional IR photographer. Gold is the "gold standard" for IR
reflectivity.