Long-exposure photography

While there is no fixed definition of what constitutes "long", the intent is to create a photo that somehow shows the effect of passing time, be it smoother waters or light trails.

Long exposures are easiest to accomplish in low-light conditions but can be done in brighter light using neutral density filters or specially designed cameras.

Increasing ISO sensitivity allows for shorter exposures, but substantially decreases image quality through reduced dynamic range and higher noise.

[5] Long exposures can blur moving water so it has mist-like qualities while keeping stationary objects like land and structures sharp.

[7] Solarigraphy (or solargraphy) is a technique in which a fixed pinhole camera is used to expose photographic paper for a length of time that is typically 6-months, but can be as short as a few hours and last well over a year.

Depending on the length of the exposure the resulting image shows the path of the Sun across the sky[8] both from dawn until dusk, but also from North to South (or vice versa) between the solstices.

Part of the Slow light: 6 months over Bristol exhibition, Quinnell describes the piece as capturing "a period of time beyond what we can perceive with our own vision.

A long-exposure photograph of a street in Carson, California , 1986. The trails along the street are from headlights and taillights , while the circles in the sky are from a police helicopter .
The central square of Rothenburg ob der Tauber , Germany , during blue hour . Notice how a long exposure blurs moving vehicles and pedestrians while buildings retain sharp focus.
In this 45-minute exposure taken on a dark clear night at Paranal Observatory , the stars leave trails as they appear to revolve around the south celestial pole (left), due to Earth's rotation .
Long-exposure photograph of a break in pool
Freight train passing through Gore , New Zealand . The 'BULB' mode on a DSLR camera was used for this photo. Note the "flashing" of the locomotive ditch lights .
A 30-second exposure showing candlelight trails in a Romanian cathedral
30-second long-exposure shot of nocturnal insects flying in front of a spotlight
Example of light painting using long-exposure shot
A 30-second-long exposure sharply captured the still elements of this image while blurring the waterfall into a mist-like appearance. Debris in the swirling water in the pool forms complete circles.
A one-year exposure showing sun trails for the entire year of 2014, taken in Budapest , Hungary