Image StackinglondonTimelapse

Aircraft over the City: Night Time Activity Patterns using Image Stacking

By November 13, 2008 One Comment

The image below is our first take at using a technique known as ‘image stacking’ to capture activities in the skies above London at night.

Comprised of 1700 photographs taken 10 seconds apart it is possible to identify City Airport (on the left) and the flightpath to Heathrow. Its not going to win any photography awards but by simply using a low cost webcam mounted inside a waterproof torch it is possible to get some interesting views of the city and the skyline.

The timelapse below strings together the single images used:

Air Traffic Timelapse over London from digitalurban on Vimeo.

Of course during the day the webcam can be used for regular timelapses, as the movie below illustrates:

London Summers Day from digitalurban on Vimeo.

Music by Ghostlight via

The movie above was captured with a frame every five seconds, making for a smooth timelapse, towards the end you can begin to note the aircraft above the skyline.

When we get back up on the roof we will take a photograph of the setup and provide details on how to make your own timelapses and stacked images.


Andy is Professor of Digital Urban Systems at the Centre for Advanced Spatial Analysis at University College London.

One Comment

  • jerome says:

    that’s very exciting! visualising trajectories could be nice as well but might require more images
    made me install evocam on a macmini just to try timelapse things and i’m now wondering about the setup of the waterproof torch