What Is Aperture?

[Demo data — development only. Specifications are illustrative; editorial copy is sample content.]

Aperture is the opening in your lens that controls how much light reaches the sensor. It is measured in f-stops, and it does two things at once: it changes exposure, and it changes depth of field.

How f-stops work

A smaller f-number (f/1.8) means a wider opening, letting in more light. A larger f-number (f/16) means a narrower opening, letting in less light.

Depth of field

Wide apertures (f/1.4–f/2.8) blur the background, isolating your subject. Narrow apertures (f/8–f/16) keep more of the scene in focus — ideal for landscapes.

Quick reference

• Portraits — try f/1.8 to f/2.8 for soft backgrounds.
• Landscapes — try f/8 to f/11 for front-to-back sharpness.
• Groups — f/4 to f/5.6 keeps everyone in focus.