Long Exposure photography

in Photo Blog Photography tips by Jamie HIBBERT — June 2, 2009 at 1:51 pm | 5 comments

Long exposure of the London Eye

Long exposure photographs

“So what is long exposure photography, and how should I use it  is a question I am being asked a lot at the moment. I thought the easiest way to explain it would be to write a brief post on the subject rather than answering each individual request.

A basic explanation of exposure is it’s the result of the 3 variables, aperture, ISO and shutter speed, used to get enough light to capture a well lit image. Generally over exposed photographs will have blown out white areas and an underexposed image will be to dark. However, both options can be used to artistic effect…

A fast exposure will almost stop time. i.e. 1/1000 s will freeze time. including very fast moving objects like racing cars. In fact a shutter speed in that region will make the tyres look like they are still and you will loose the effect of the car racing.

So already we need to balance shutter speed to capture more of the emotion of the image, rather than just a snap shot of time. The above refers to fast moving objects. but it can be applied to anything, people, water, seascapes, trees and clouds for example. So by increasing the exposure time we can add a new element into our photography, capturing time it’s self!

Here are a few ideas:

1. Long exposure of large bodies of still water will remove wavelets and make it look mirror smooth.
2. Cloud will track in the sky.
3. The sea will look soft and more like mist.
4. Trees will show the effects of the wind.
5. People will move around town scapes, showing action.
6. Car headlights will turn into traces.
7. Stream and water falls will look soft and inviting.
8. Special effects with light sources can produce interesting abstract photography.

Considerations of long exposure photography

The primary problem will be camera shake. So you need to purchase a stable tripod to get crystal clear images. This is because the amount of time your shutter is open will be increased and any slight movement will be captured. Some long exposures can last 10′s of minutes.

Increasing exposure time in bright light can be a problem. Your camera ISO is as low as it will go, your aperture is stopped down as far as you want it, yet because of the amount of natural light the exposure time is still only a few seconds. The way around this is with the use of filters over your lens. You can buy a number of filters which will reduce the amount of light entering your camera. For long exposures in strong light you might consider a 10 stop filter. These filters were design for taking images of strong light sources, like furnaces, but work very well for creating long exposure photographs in bright daylight!

image from: wilfried.b’s photostream