To create a traffic light trail time-lapse at night, mount your camera on a tripod above or beside a busy road, use long exposures of a few seconds each, and let an intervalometer take a frame every few seconds for an hour or more. You then assemble the frames into a video. Settings below are general guidance, so adjust them for your location.
Gear and Location
- A camera with manual mode and a sturdy tripod.
- An intervalometer, either built in or an external remote.
- Spare batteries and a large memory card, since you will take hundreds or thousands of frames.
- A wide or standard lens, depending on the view.
- A legal, public spot with a clear view of a road, such as a bridge walkway, hillside or rooftop where you have permission.
Keep yourself and your gear well away from traffic lanes, and follow local rules about where you may set up.
Step by Step
- Arrive at dusk. Blue-hour light gives a nice sky and lets you test your composition while there is still some visibility.
- Frame the shot. Include a curve, junction or intersection so the trails have shape. Level the camera with the tripod bubble or in-camera grid.
- Switch to manual mode. Use manual exposure and manual focus so nothing changes between frames.
- Set the exposure. A general guide is ISO 100 to 400, aperture f/8 to f/11 and a shutter speed of roughly 2 to 8 seconds. Longer exposures create longer trails.
- Focus manually. Use live view on a distant light, zoom in and adjust until it is sharp, then do not touch the focus ring.
- Turn off noise reduction and image stabilization. Long exposure noise reduction doubles the time between frames, and stabilization can blur tripod shots.
- Set the interval. Make it about one second longer than the shutter speed, so the camera has time to save each frame.
- Shoot a test frame. Check the histogram and zoom in on the trails and focus.
- Run the sequence. Plan for 300 to 900 frames, depending on how long a clip you want.
Assemble the Time-Lapse
Import the images into your video editor or a time-lapse tool as an image sequence. At 24 or 30 frames per second, 300 frames gives roughly 10 to 12 seconds of video. Apply a consistent color edit to all frames before export, and consider blending frames or using stacking to make trails look smoother.
Exposure at a Glance
| Setting | General range |
|---|---|
| Mode | Manual |
| ISO | 100 to 400 |
| Aperture | f/8 to f/11 |
| Shutter | 2 to 8 seconds |
| Interval | Shutter time plus about 1 second |
FAQ
What if the sky becomes too bright or too dark?
During dusk, light changes quickly. Shoot after the sky has gone dark for the steadiest exposure, or learn to ramp exposure gradually in an editing program.
Can I do this with a phone?
Some phones have long exposure or light trail modes. Use a small tripod and an app that can take interval shots.
The Short Version
Use a tripod, manual settings and an intervalometer to capture a few hundred long exposures of passing traffic, then combine them as an image sequence. Choose a legal spot well away from traffic, and test focus and exposure before you run the full sequence.
