Time Travels

Want to Reveal the Invisible? Try Long Exposures

- Deborah Sandidge

WANT TO SEE SOMETHING YOU DON’T SEE EVERY DAY—something, in fact, you can’t really see at all?

I’m talking about the passage of time— well, really the cumulative effect of what’s happening over time—captured in one image. Long exposures will allow you to do that. They can be comparatively long—a half second rather than, say, 1/125 or 1/250 second—or really long; one of the photos here took five-and-a-half minutes. Here’s how it works.

I start by visualizing what’s likely to happen in the scene over a period of time. I have to take into account several things when I compose the shot. Depending on the scene and the situation, that could be the speed of clouds moving across the sky, the flow of water in a stream, the rush of waves to the shore. Then I set up my camera and tripod to capture what I imagine, or expect, will take place.

My first step is to meter the scene and take a properly exposed image based on the depth of field I want for the image. I usually go for a lot of depth of field, so my f/stops for this type of photography are generally in the f/11 to f/22 range.