Turning a webcam into an infrared camera

Turning a webcam into an infrared cameraThe sensors in digital cameras pick up more than just visible light. They pick up a lot of infrared too, that's light below red that we're not able to detect with our eyes.

This can make pictures look funny, so manufacturers add a filter to block the infrared and give you a more natural image. Actually the filters don't do a perfect job and if you fire a TV remote control at your camera phone you should see it light up on the screen.

All this means you can have a bit of fun with your old web cam. You can remove the infrared filter then add a visible light filter so your webcam only sees infrared!

There are loads of different makes of webcam but most of them have a bit that looks like this:

Turning a webcam into an infrared camera

It's the lens assembly. The end you can see is the end that sticks out of the webcam. At the other end is the IR filter.

I was able to slice off about 1mm from the end to release the filter using a stanley knife:

Turning a webcam into an infrared camera

Then it just screws back into place.

So now you're letting in the infrared all you have to do is block out the visible. You can buy a special filter for the job, or (thanks to Alby Reid) you can cross two polarising filters because these generally only block out visible light. Try the lenses from a pair of 3D glasses (with ReadD branded glasses you'll need to flip them around in all different combination until you find the one that blocks light. That's because they filter circularly polarised light and are a little more complicated than straight polarisers) Here's my setup:

Turning a webcam into an infrared camera

For a while I wasn't seeing anything, just a black screen. Then I realised all the light in room was from energy saving lightbulbs which give off no infrared. I switched to an old style incandescent bulb and the room lit up!

Here are some weird looking things (click to enlarge):

Turning a webcam into an infrared camera

I think my Mona Lisa might be a fake!

Turning a webcam into an infrared camera

Only the Queen is left when you take away visible light:

Turning a webcam into an infrared camera

And here's my eyeball:

Turning a webcam into an infrared camera

Plants aren't that into infrared:

Turning a webcam into an infrared camera

  • Liam120

    Plants are into Infrared, it’s the light whites in the shots which are purporting infrared, hence light. The darker areas are not reflecting infrared.

    So the foliage is reflecting the most infrared.

    Just to put you right. ;-)

    • http://stevemould.com Steve Mould

      Ah, you see that’s why I’d say they’re NOT into infrared :) . They’re not absorbing it but instead rejecting it. Depends how you like to anthropomorphise I guess. By my logic plants aren’t that into green either.

  • towelinmonk

    Oh, also, I use this hack for a science show and I found that if you can’t get any polarising filters, then an exposed negative from old camera film works too.

    Although to be honest, it’s probably harder to find that then 3D glasses…but it’s another option!

  • http://www.ipaidnothing.co.uk/ Alex @ Free iPhone 4S

    That’s awesome! I knew about the TV remote control camera trick, but never would have thought about taking the filter out. 

    Why isn’t there more of this on the internet?!

  • Svenmills

    And the magpie is invisible in IR, too…. to figure!

  • Froggels

    As a filter you can use old black (exposed) developed negatives or unexposed developed slide film. Both can still be purchased in stores (at least here in Germany) Remember they need to be black; therefore over-exposing “normal” negative colour film will turn the negatives black and not exposing slide film will leave it black. I found that the slide film works better, possibly because it was designed with the intention of shining visible light through it.

    The material from floppy disks also works if you have any lying around.

    • http://stevemould.com Steve Mould

      This is a great tip. Thanks Froggels