What this is
Aperture is the opening inside your lens that lets light reach the camera sensor. Measured in f-stops, this setting does more than control exposure. It also determines your depth of field, which is the zone of acceptable sharpness from foreground to background in your final frame.
What you need
- A digital camera with manual exposure modes
- A versatile lens with a variable or fixed maximum opening
- A sturdy tripod for low light or long exposures
- An understanding of your lens focal length and minimum focus distance
Step by step
- Switch your shooting mode to Aperture Priority or manual to take direct control over the size of the lens opening.
- Select a wide opening like f/1.4, f/1.8, or f/2.8 when you want to isolate a portrait subject against a softly blurred background.
- Choose a medium opening between f/4 and f/8 for street photography, casual group shots, and general travel scenes where you need moderate sharpness.
- Turn to a narrow opening like f/11 or f/16 when shooting landscapes to ensure both the near foreground and distant mountains stay crisp.
- Avoid using the smallest openings such as f/22 unless necessary, because diffraction can soften your entire image.
- Check your shutter speed after adjusting the lens opening to make sure your image will not suffer from motion blur.
- Review your test shots on the camera LCD screen, zooming in to verify that your critical point of focus is sharp.
Tips
- Portraits. Use wide settings like f/1.8 to blur distracting backgrounds and make your subject stand out.
- Landscapes. Choose f/8 or f/11 to maintain edge-to-edge sharpness across the entire frame.
- Low Light. Open your lens as wide as possible to let in maximum light and keep your ISO settings lower.
- Action. Balance a wider lens opening with a fast shutter speed to freeze fast-moving subjects clearly.
- Macro. Use narrow openings carefully with a tripod since close-up work yields very shallow focus zones.