Low light shots in towns and cities offer a multitude of creative opportunities and exposure challenges in equal measure. High contrast between the dark environment and bright artificial light can make calculating exposure tricky. However, this contrast allows artistic use of very defined points of light, such as car headlights and street lamps, to produce photographs with added interest. A popular technique is to use the diffractive properties of very narrow aperture settings to render these lights as eye-catching ‘starbursts’, which can be used to create images with a dreamy, fairytale atmosphere.
This ‘look’ is applicable to any low-light urban landscape, where the photographer is aiming to create shots with a difference - this effect is not something we see with our own eyes, so it easily draws and holds a viewer's attention. Without the proper use of f/stop, lights will remain diffused bright areas, devoid of form and structure, which does not suit every composition.
By varying aperture, the extent of the diffraction of lights can be controlled, altering the effect strength, while focal length changes the size of the lights within your composition. With the correct subject matter and a subtle balance of effect strength and environmental interest, this technique can breath life into otherwise flat and dull scenes.
1- Select aperture-priority mode
Set A (or Av) mode from your camera’s main shooting mode dial which will allow you to control f/stop while the camera monitors shutter speed for exposure. Set ISO 400 as a base setting from which to work.
2- Use a tripod
Due to the need to utilise a small aperture to create the starburst effect and the low ambient lighting, a tripod is recommended to keep images sharp. Try test compositions before affixing your camera
3- Stop down the aperture
Use the camera’s control dial to set a narrow aperture. Start at f/16 for a balance of effect and diffraction blur and only go to f/22 or beyond if you need a stronger, more defined effect on your lights
4- Adjust your exposure
We need to create good contrast between the lights and background. Underexpose slightly using exposure compensation to produce a darker, dramatic atmosphere, so the diffracted lights stand out for depth
5- Place your subject
Use live view to compose your image, placing your subject within your pre-arranged background. Try varying subject position, overlapping them with the lights in some shots to experiment with flare effects
6- Shoot and review
The small aperture will produce deep depth-of-field, so shoot multiple images to ensure a clean background, free of distractions. Increase the f/number further if the effect is not yet strong enough.