What is the adjustable opening of a camera lens called?

• A. Shutter speed
• B. F-stop
• C. Focal length
• D. Aperture

Answer: (D)

The adjustable opening in a camera lens is called the aperture. It acts like a pupil for the lens, controlling how much light reaches the sensor. A wider aperture lets in more light and gives a shallower depth of field, while a narrower aperture lets in less light and increases depth of field. The term f-stop describes the setting that you adjust to change the aperture size, but the actual opening itself is the aperture. Shutter speed, by contrast, controls how long the sensor is exposed to light, and focal length affects the lens’s zoom or field of view, not the size of the lens opening.