DIY Infrared Photography
It’s a little known fact that most digital cameras can actually see infrared light. You can easily prove this to yourself by pressing buttons on your remote control whilst pointing it at a digital camera. For example, here is my remote control:
This suggests that given a suitable filter it would be possible to do IR photography with a normal digital camera! Luckily most houses do contain such a thing in the form of the negatives that used to be supplied with developed photos*. At the end of the negatives there is often a small black section. This is film that has been completely exposed and then developed.
This bit of the negative blocks out almost all visible light, but lets through IR. To completely block visible light you need two layers of this stuff, which you can then sellotape onto the front of a camera to create a cheap IR viewing device!
I found that in order to get good photographs the camera needed long exposure times (and therefore needed to be supported on a solid base to avoid blurring. Foliage, in particular, looks ghostly since leaves reflect strongly in the IR. Here are a few of my pictures:
Unfortunately light was slipping in from both sides of the filter and I didn’t notice this until it was too late!
* maybe they still are, but I don’t know anybody with an analogue camera any more
Comments
Comment from Chris
Time: May 10, 2007, 12:56 am
I couldn’t get it to work. What kind of lighting conditions did you use? I tried it indoors.
Maybe my camera filters out infrared…
Comment from jeg
Time: May 10, 2007, 8:48 am
this is great, thanks craig.
Comment from cmb
Time: May 10, 2007, 10:01 am
jps: The only other thing I noticed is that people’s eyes look like big black pits, like the nighttime scenes in the Blair witch project. It’s really creepy!
Chris: You definitely need to be outside, I couldn’t get a single image from indoors. Additionally some more expensive cameras do have IR filters in their lenses so it’s worth checking if you can see the light from the remote control before testing anything else.
Comment from cmb
Time: May 10, 2007, 10:34 am
One last thing, this graph shows reflectivity as a function of wavelength for a few common materials:
http://www.wrotniak.net/photo/infrared/_img/ir-refl.gif
The biggest changes are that in the IR foliage is really bright and water is really dark.
Comment from Max
Time: May 11, 2007, 8:02 pm
Holy moly! That is cool.
Comment from jps
Time: May 14, 2007, 9:36 am
I’ve seen it, its true!
Comment from Tim
Time: September 26, 2007, 6:33 pm
just to show, my bog standard digital cam with a lcd display shows infra red, dont even have to take the photo (did the remote test) very interesting indeed.
Comment from jps
Time: May 9, 2007, 11:30 pm
that is so cool! can you try it at night, illuminating things with your remote? is there anything else you can only see in ir rather than visible?