LAMY - HOW IT WAS MADE

This photo was taken during late twilight.The exposure was about 5 minutes long. The red streaks are car tail lights passing by on US 285.

I actually stopped several exposures midway and started again only after oncoming cars had passed by. It is possible to put the cap back on your lens and then remove it during long exposures to keep unwanted cars, planes, etc. from exposing on your film. Beware, there are several things that could happen while using this technique: every time you touch your camera while the shutter is open you risk moving it, and stars that are bright enough to expose on film will have a gap in their trails during the time the lens cap is in place.