A long exposure is a photograph taken with the shutter held open on purpose, from a fraction of a second to hours, so that anything moving smears into trails or vanishes while anything still stays sharp. The camera sits on a tripod, and the time does the work: water turns smooth, headlights become lines and stars draw arcs.
The full guide is long exposure photography. It explains why a long exposure is an average of everything in front of the lens, which shutter speed suits water, clouds, traffic, crowds and stars, how to work out the time with an ND filter, and the step by step order for a clean frame. Start there if you want to understand the technique. The two pages filed under this one go further into particular jobs.
Light trails
Cars disappear from a long exposure and their lights stay. Light trail photography covers where to stand and when, the shutter speed for the traffic in front of you, fixing trails that burn out to white, timing each exposure, and stacking several frames into one.
Working faster in the dark
At night the waiting adds up: every frame takes a minute or more, and noise reduction can double it. Speeding up a low-light long exposure workflow is about the time around the exposures: settings fixed before you leave, when long exposure noise reduction is worth its cost, exposing for cleaner files, and processing a whole sequence at once.
Other doors from here
- Only have a phone? Phone long exposure shows how the built-in modes blur water, lights and crowds.
- Exposures longer than 30 seconds need bulb mode, which keeps the shutter open as long as you choose.
- Choosing a filter for daylight? The ND filter guide covers strengths, types and color casts.
- For minutes rather than seconds, shooting and processing a super long exposure covers the filter arithmetic, keeping the camera still for minutes and processing the result.
- Pointing the camera at the sky? Star trail photography covers location, settings and stacking.
- Waterfalls and streams have their own page: how to photograph waterfalls.
- Drawing with a flashlight while the shutter is open is light painting.