Long-exposure photography involves using a long-duration shutter speed to capture the stationary elements of images while blurring, smearing the moving elements. Long-exposure photography captures one element that conventional photography does not: an extended period of time.
The paths of bright moving objects become clearly visible—clouds form broad bands, vehicle lights draw bright streaks, stars leave trails in the sky, and water & waves appear smooth. Only bright objects leave visible trails, whereas dark objects usually disappear, if you have people in your chosen composition a long exposure will make them disappear. Boats in long exposures disappear during the daytime, but draw bright trails from their lights at night.
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. When using a neutral density filter your camera’s auto focus will not be able to function. It is best to compose and focus without the filter. Then once you are happy with the composition, switch to manual focus and put the neutral density filter back on.
Visit the location well in advance
Scout the location ahead of time, as you need time to find the perfect composition or at least more than the time needed for a “short exposure”. In fact, in a long exposure, the world is completely different from how you see it with your own eyes. You have to try to see it with your mind, looking for a harmonious composition that includes moving subjects, trying to predict the direction of the clouds or the force of the sea. Try not to put the sun into the composition because its movement will ruin the shot and it will create an area of overexposure that is not recoverable. If you cannot avoid the sun, wait for it to hide behind a cloud.
- A camera that you can set to manual control
- A sturdy Tripod
- A torch with a Red Light will help with your night vision
- An Intervalometer if your Exposure is more than 30 seconds
- A Neutral Density Filter (3 to 10 Stops) if photographing long exposures during the day
Setup and take a long exposure
Choose your location, it could be a waterfall, a lake, or a landscape with nice moving clouds.
The first thing once you arrive at your chosen location is to take a few minutes and take a good look around and chose your composition, setup your camera and tripod only when you have your chosen composition, take a meter reading either using your camera’s meter or as I do a hand held light meter, (if you were to have a metre reading of 1/60 of a second and you are photographing a waterfall you would need at least a 4 stop ND Filter to give you a 1/4 second exposure) this is a starting point and you may need a 6 or 10 stop ND Filter depending on how much you want to slow down the water. use either a remote shutter release or the two second timer to stop any camera shake, if your camera has a mirror lock up, lock the mirror up first.
Long-exposure photography is often used in a night-time setting, where the lack of light forces longer exposures, if maximum quality is to be retained. Increasing ISO sensitivity allows for shorter exposures, but substantially decreases image quality through reduced dynamic range and higher noise. By leaving the camera’s shutter open for an extended period of time, more light is absorbed, creating an exposure that captures the entire dynamic range of the digital camera sensor or film. If the camera is stationary for the entire period of time that the shutter is open, a very vibrant and clear photograph can be produced.