Looking back to our process of making a multitouch table, the camera seems to be the most delicate part and a source of many (at that time very unfocused) woes.

We started with an old Logitech QuickCam Pro 4000 (or something similar) that we got to play with. Not the best webcam in dark environment but we hoped that the whole thing will somehow work. We were wrong. There were many problems with that camera. The first one was my poor IR filter removal attempt that resulted in scratched lens and unfocused image. The second was low framerate – quite unsuitable for serous human-computer interaction. And the worst of them: the sensor of that camera is just not sensitive enough when it comes to IR light. Well, it is a low-cost webcam after all.

So we decided to do a bit of research regarding low-cost cameras used in multitouch community. The best price-performance camera on the market at that time seemed to be PS3 Eye camera. So we decided to order it on the Internet (sadly this camera is very hard to get in Slovenia at the moment). The price of about 25€ (I did not do the ordering so I do not know the exact price) seemed very reasonable. Unfortunately there were some delays with shipping, that were also the cause of delays in our overall project, but at the end we finally got the camera.

Disassembling PS3 Eye camera is a great deal more difficult than Logitech QuickCam Pro 4000. I had to check a few guides on the Internet to be sure and you actually have to break some plastic to get it open. After that it is pretty easy. Remove the IR filter (small circular glass thingy between the lens and the sensor) and insert IR pass filter in its place. And surprise, surprise: suddenly everything worked really, really well. Actually we even had to reduce the voltage to the IR diodes (before we had the whole thing set to the very maximum) to reduce a very intense glow.

The best thing about PS3 Eye webcam is that it works very well even in low light environment. Sure there is noise, but you can get more than 30fps out of it. Now, we have not made many tests at this time, but the whole thing just may be very responsive. So the lesson of this post is: it DOES matter which webcam do you use if you want to make a multitouch surface.