Interactive
Aperture Simulator
Watch depth of field, background blur and exposure change as you open and close the aperture.
Lens opening
f/2.8
2.4 stops less light than f/1.2
Aperture
Depth of field
- Near limit
- 2.73 m
- Far limit
- 3.33 m
- Total DOF
- 0.60 m
Wider apertures (small f-numbers) blur the background more and let in more light. Narrow apertures keep more of the scene sharp.
What you're seeing
As you open the aperture (smaller f-number), more light reaches the sensor and the background blurs more. Close it down (larger f-number) and less light arrives while more of the scene stays sharp.
The lens opening is shown as a hexagonal iris — a real aperture is formed by overlapping blades that create a roughly circular opening.
Two effects, one control
Aperture is the only exposure control that changes both brightness and the look of the image. Wide apertures (f/1.2–f/2.8) are favored for portraits; narrow apertures (f/8–f/16) for landscapes.