Public Lab Wiki documentation

Webcam filter removal

This is a revision from February 02, 2012 14:56. View all revisions
3 | 7 | | #741

$8 Creative Notebook Live Webcam

Someone ought to post a video about this mod, but for now here is a Q/A based on a thread on the mailing list:

Is there a UV filter that I need to remove from the camera?

There is an IR/infrared filter. It probably blocks some UV too.

If so, do I need to open the case on the camera?

If you want broader band readings, yes. But it is still quite functional as a visible-range spectrometer otherwise.

I’m not quite sure the best way to do that, although I did manage to get one of the clear clips to pop off.

That one is a bit tricky -- first, just yank the plastic lens cover off; it seems a bit violent but you won't damage the lens -- inside it's actually an aluminum tube with an aluminum lens holder screwed and glued into it (I was struggling with it and tried using my teeth, which is how I found out it was aluminum, owwwww).

But I was successful in using a large pair of pliers to firmly grip the lens holder and unscrew it. Be careful not to crush the aluminum tube. Once you unscrew it, the infrared filter is a small piece of reddish glass glued (inside a metal ring) to the back of the lens holder. It's extremely well glued on there, and I eventually used a table clamp to grip it and yank it off with brute force, breaking the filter. After thoroughly cleaning up the bits of the broken filter (it shattered), I screwed the lens back in.

I know this sounds a bit involved, and we've found cameras which are much easier to modify. But this camera is HD resolution and is extremely compact and very low cost -- in short, it's the perfect camera for this kit. It even has a flat side perfect for mounting it inside the spectrometer case. So until a "more ideal" camera comes along, I think we need to post a video on the filter removal to guide folks through it bit more.

If you're unsure of the modification, I recommend using it as-is for a bit before trying it.