Time-lapse photography using a cheap webcam

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Update: September 2002

I knocked together some scripts to do time-lapse films from the BBC's Cambridge web cam. Also, here are some films by Nick Thompson; you'll need `Flash' to view them.

Update: January 2003

Just found this rather splendid page with time-lapse film of canal locks. Cool.

Update: July 2003

These animations are pretty cool, too; check out the train one. (Made with a Canon Ixus digital camera, and they look pretty good.)

A little while ago, I bought a Philips `ToUCam Pro' webcam (I can't supply a link to the product's web page, since the Philips website requires some sort of session token to look at any products; you can find it by searching for `PCVC740K'). A webcam seemed like a fun thing to have, and the Philips one appeared to be the best available at the time, despite a collection of significant deficiencies:

The last of these is a significant problem from the point of view of making time-lapse films (indeed, for any application where two or more photographs must be taken from roughly the same vantage point). However, it proved to be quite easy to cobble together a more functional stand for the thing.

Carpentry for dummies

Stand for Philips PCVC740K camera, made out of wood, string and clamps. Oh, and a radiator. Detail of stand for Philips PCVC740K camera

One quick trip to Homebase later, and now I feel prepared for a full-scale rant about DIY stores. But back to the matter at hand:

Firstly, the camera itself can be mounted on a short length of 6mm dowel, by unclipping it from the supplied stand and inserting the dowel in the bottom of the camera housing. The hole is actually slightly smaller than 6mm across, but whittling the dowel down a bit using a blunt knife was sufficient to fit it in place. This approach has the advantage that the camera can still be used with the original stand, though why I might want to do that escapes me.

Of course, the mounting socket on the camera is at a random angle to the camera's optical axis (presumably for some stupid marketing reason); obviously the correct way to deal with this would be to drill an appropriately-angled hole in a bit of wood and glue the dowel in place, but I found that string and a little hand-clamp were sufficient.

Then, mounting the camera itself is achieved using a bit of 21mm square timber, clamped to a solid object -- in the picture above, a radiator.

(Note that this appalling piece of handiwork is, by my standards, a pretty sophisticated bit of carpentry. I didn't use gaffer tape once, for instance. But seriously... clamps are great.)


I used vgrabbj to grab the images; there doesn't seem to be too much wrong with it. I used a tiny shell script to drive image capture, rather than vgrabbj's `daemon mode', since the latter wasn't really suitable for the purpose. To encode the movies, I used the Berkeley MPEG Encoder, which works well. I still don't know what most of its tunable parameters do, and I'm not prepared to spend too much time writing the nasty FORTRAN-style control files to figure it out.

Roll up, roll up, for a once-in-a-lifetime experience!

Right, here's the bit where I hasten the demise of the internet by inviting you to download giant MPEG movies of boring stuff happening.

(Dull technical details. OK, I admit, everything so far has been dull technical details. Nevertheless... the films below are MPEG1 streams with a nominal frame rate of 24fps. If you are running on Unix, then the freely available mpeg_play program can cope with them just fine. On Windows, it appears that Microsoft Media Player can do the job too. I don't know, or very much care, about other platforms.)

Copyright (c) 2001 Chris Lightfoot. All rights reserved.