How I learned to paint with light

When photographer Jeff Thompson and I went into the Wabasha Street Caves last week with geologist Greg Brick, Jeff captured an awesome photograph — and I learned about light painting.

The technique Jeff used involves snapping a photo with little or no light and keeping the shutter open for a longer exposure. During that exposure (15-30 seconds), a helpful assistant (me) walks through the shot holding small lights (headlamps) to create the swishing light effect.

For this photo, we had two musts: Greg had to keep very still so he wouldn't blur and I had to never stop moving, lest any part of me show up in the photo. If you look closely, you might see ghostly images of me while I moved around.

Light painting is not new — you could easily spend hours on the Internet gawking at some beautiful compositions. But it was new for me.

After we had Greg's shots, we tried the same technique with me playing both roles. It's hard to be the focus of a shot and a light painter at the same time — I'm apparently too jumpy to avoid a blurry mess.

(MPR News photos/Jeff Thompson)

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