time exposures

Historical Posting – Originally published in 2004 – Since this is an archived story – products mentioned may not be available or even made any more – Let us know if you have any questions.

If you have a “B” setting on your camera, one of the fun things you can do is to take time exposures. It’s easy to do if you keep several important points in mind. Plan to experiment and have fun. Use your imagination! There are not real hard and fast rules to time exposures, so relax, shoot a lot of film and experiment.

• Subject. Good subjects for time exposure include just about any bright light source such as traffic patterns, amusement park rides, speeding trains, fireworks and even ships passing in the night. Stationary light sources such as neon signs or holiday illumination can also be time photographed through a technique called “zooming” (see below).
• Photographing light trails is dependent on keeping the shutter open for an extended period. The correct duration depends on length of exposure, lens focal length and subject distance. Traffic patterns could take anywhere from a few seconds to a minute depending on the distance to the subject and its speed. Amusement rides require a significantly shorter duration. The passing ship will require extended duration because of the speed of the vessel and its distance from the camera.
• When the angle of view is wide, the exposure must be longer to capture movement because it takes the subject longer to pass through the frame. Conversely, using a telephoto lens isolates a smaller part of the scene, so the exposure is shorter.
• Be sure to use a tripod and a cable release to avoid camera shake.
• Determining exposure time. The best way to measure exposure is to read a middle tone in the scene. A car’s taillight is an excellent starting point. After you measure the exposure, set the duration to the time it takes for the subject to move through the frame. Then set the correct aperture for that time.
• Traffic Patterns. Twilight is an optimal time to capture traffic patterns. Try to position yourself slightly above the traffic. Don’t compose the scene where headlights are shining directly into the lens or set-up on ground affected by traffic vibration. Try to photograph the taillights for saturated red streaks. When using ISO 100 film, eight seconds at f/8 is a good starting point.
• Amusement Park Rides. Exposure duration should be based on several rotations of the ride. The longer the exposure, the smoother the light will be. Find a position that allows you to include the entire ride. When using ISO 100 film, try an exposure of two seconds at f11 and bracket exposures.
• Boats. Compose the scene like a city scape or landscape. The light trail is more of an accent than the main subject. Make the longest exposure possible. It could require an exposure of several minutes.
• Zooming. Zooming allows you to procure streaks from stationary light sources such as neon lights, pin-lit trees and holiday lights. The best sources are bright lights against dark backgrounds. Zooming is not an exact science, so the results may vary. The most popular method is to begin in the wide angle setting, then slowly zoom in to the telephoto setting. The camera does not have to be on a tripod, but it helps. The exposure duration for zooming is significantly shorter than light trails in motion. Basically, you set the shutter speed between one and four seconds, then set the aperture accordingly.
• Many of today’s modern SLR cameras are equipped with incredible abilities to take time exposures automatically. If you have one of these cameras, try setting it on “Aperture priority” with the smallest setting available on your cameras (F22). Use your flash and set it to “rear curtain sync” for spectacular results. With a little practice you’ll achieve a blending of the light in the background, with your subject “flash frozen” in the foreground.
• Many of the sophisticated point and shoots also have “night photography modes.” If you have not experimented with this setting on your camera, be sure to give it a try.
• Helpful Accessories. BCC has a variety of accessories to help you take more dramatic time exposures. These include tripods ($14.95 and up) and monopods ($29.95 and up), cable releases ($11.95 and up), and bean bags ($20 and up) for steadying your shots plus the Black Cat Exposure Guide ($19.95) and the Kodak Pocket Photo Guide ($12.95) to provide advice on any exposure setting for almost every possible shooting situation.

Tom’s Rules For Time Exposure:

1. Have fun.
2. Use your imagination.
3. Bracket your shots.
4. Shoot a lot of film!