Introduction: Infrared Digital Camera - the Real Way
Are you tired of at looking at the world in boring, ordinary colors? Upset about the limitations of your eyeballs to perceive light between 400 - 700 nm? Odds are you have a perfectly good infrared imaging device sitting around and you don't even know it. Here's how to modify your average digital camera to unleash its full infrared capacity. All you need are some lighting filters, a small screwdriver, and steady hands. In no time flat you'll be taking dreamy, surreal IR pictures.
Step 1: Get Yourself a Crappy Digital Camera
So here's the thing about infrared. The CCD on your average ordinary digital camera absorbs infrared light quite effectively, so much that camera manufacturers try their hardest to block IR from ever reaching the detector. Digicams have an IR-blocking filter behind the lens that mops up most (but not all) infrared from getting through. Therefore, possible ways to take an infrared picture are (1) exploit the low IR sensitivity of an unmodified digicam by placing a filter in front of the lens that blocks out everything *but* infrared, or (2) enhance the IR sensitivity of the camera by taking it apart and physically removing the IR-blocking filter.
Option (1) is certainly easier, and a number of instructables use that principle:
Infrared Ir Webcam
Take Infrared Pictures With Your Digital Camera
A better diy infrared filter
But there are some drawbacks to using an unmodified camera. Typically the exposure times are so long (1 second or so) that you need to use a tripod. Option (2) is more effective and you can take better IR pictures, if you're willing to take your camera apart.
Here's the catch. This project isn't difficult per se, but it involves handling a lot of small and fragile camera parts. There's a very real chance that one little slip up could turn your nice digicam into a very shiny brick. So don't try this on a camera unless you're willing to accept the risk of breaking it. I got this used VuPoint 3.1 MP camera at Ritz on the cheap. Used cameras also tend to be very inexpensive on eBay. If you have an expensive digital SLR you want to convert, you might consider paying a professional (like this place) to do it for you, which costs ~$300.
You will also need a lighting filter to block out all visible light except for red and longer wavelenghts. For this I am using "Congo Blue" (Lee #181 or Rosco #382) available from B&H for about $10 after shipping.
Step 2: Open the Case
Pick up that screwdriver and start taking screws out. The ultimate goal is to access the IR-blocking filter that's right in front of the CCD. The exact components you'll need to take out in order to get there will vary from camera to camera, so I will only offer some generic tips:
- get a plastic container (I used an ice cube tray) to put the screws in as you take them out. There are a lot of little screws and you will never remember the order you took them out unless you organize them somehow.
- take pictures as you remove screws. This will help when you go to put the camera back together. Again, there are a lot of screws and it is incredibly helpful to have a photographic record of what went where.
Step 3: Start Removing the Boards
On my camera there was a separate board in front of the main one that had the lens/CCD assembly. I had to take out 6 screws in order to get it off. Take a picture every time you remove a screw. Oh and watch out for the big capacitor that is full of electricity.
Step 4: Remove the CCD Assembly
After separating the main board from the case, I had to remove the LCD display in order to liberate the lens/CCD assembly. Be careful with the ribbon cable that is especially fragile.
Step 5: Locate the IR-blocking Filter
Once you've gotten to the heart of the camera and located the CCD, you're almost ready to get down to business. We want to locate the IR-blocking filter and remove it. I've seen this procedure done on 3 different cameras, and on each the IR-blocking filter was in a different place. So I can't say exactly where it's going to be on your camera, but it's pretty easy to spot. The IR-blocking filter is a thin (~1mm or so) piece of glass that gives a nice blue reflection depending on the angle you hold it.
On my camera, the IR-blocking filter was embedded in the lens assembly. It was the last optical component of the lens before the CCD. On the other two cameras I have seen dismantled, the filter was directly in front of the CCD. This is the point of no return. Once you take out the filter you will not be able to restore the camera back to normal. It took me a minute to convince myself I had located the right component, and like I said the faint blue color is the best giveaway.
Step 6: Take Out the IR Filter
Remove the IR-blocking filter by any means necessary. Unfortunately, this ended up being a real pain on my camera, because the filter was embedded in the plastic lens assembly. First I had to remove the lens from its enclosure by unscrewing it (I drew a line down the threads so I could reassemble it correctly). Then I cut away part of the plastic with a knife in order to pry out the filter. In the process, I cracked the filter and it came out in pieces. It ended up not mattering since none of the lens optics got scratched, and the filter is going in the trash anyway.
Hopefully it will be easier to take out the filter on your camera. I have seen others where the IR-blocking filter is right in front of the CCD held in place with glue, and it's a piece of cake to remove it.
Step 7: Install Congo Blue Filters
Now we want to install a filter that will block out all the light of the visible spectrum, only allowing infrared to reach the CCD. We do this by putting 6 layers of the Congo Blue filter gel behind the lens. Cut the filter gel into a bunch of little squares that will fit snugly inside the lens assembly. Pick out the 6 best ones, and install them inside lens before mounting it back in place in front of the CCD.
The material the filter gel is made out of is kind of fragile, and has a tendency to pick up scratches and dust. In my experience it's also really static sensitive, which is annoying. I wore a pair of latex gloves to avoid getting any fingerprints on it, and I handled the squares with tweezers. Even so, it took 15 minutes to wrestle them into place.
Another point here, with some cameras (especially nicer onces that have zoom), removing the IR-blocking filter can mess up the autofocus. Other sets of instructions I have seen recommend installing a piece of ordinary glass about the same thickness as the IR-blocking filter that you removed. I didn't do that, since my camera was fixed focus and not very good to begin with. But if you want to, the easiest way is to cut a microscope slide with a glass cutter to the right size, and install that behind the lens.
Step 8: Reassemble Your Camera and Go Use It
Now that you've got the IR-blocking filter removed, and the Congo Blue filters in place, you're almost ready to start taking pictures. Reassemble your camera by doing everything up until now in reverse. You were taking pictures of all the screws you were taking out, right??
Once everything is put back together, cross your fingers and turn it on. With any luck it will power up and be ready to use. Go outside and take some pictures! Outdoor scenes with lots of trees and grass look especially cool. I took a trip to Point Reyes National Seashore and took some sweet pics, in this flickr photoset. Also a trip to the Russian Ridge open space preserve in this photset.
Thanks/props goes to Zach S. for helpful tips found on his site.