Aperture is the adjustable opening inside your camera lens that lets in light. You can think of it like the pupil of your eye — it opens wider in low light and narrows in bright conditions. In photography, aperture is measured in f-stops, such as f/2.8, f/5.6, or f/11.

Smaller f-stop numbers (like f/1.8) mean a wider aperture, allowing in more light and producing a shallower depth of field. That’s great for portraits with blurry backgrounds. Larger f-stop numbers (like f/16) mean a narrower aperture, which brings more of the scene into sharp focus — useful for landscapes.

Why It Matters

Aperture affects:

  • Exposure: A wider aperture brightens the image.
  • Depth of field: Affects how much of your image appears sharp.
  • Image style: Helps create dreamy backgrounds or crisp detail throughout.

Together with shutter speed and ISO, aperture forms the exposure triangle — the three core settings that control brightness and image quality.

Tips for Beginners

  • Use wide apertures (f/2.8 or lower) for portraits or low-light scenes.
  • Use narrow apertures (f/8–f/16) for landscapes or group shots.
  • Learn how f-stop numbers work — they can be confusing at first!

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