Which camera control determines the amount of light that reaches the sensor?

• A. White Balance
• B. ISO
• C. Shutter Speed
• D. Aperture

Answer: (D)

Aperture is the opening in the lens that controls how much light can reach the sensor. Its size, described by f-stop numbers, directly changes the light entering the camera: a larger opening (lower f-number) lets in more light for a brighter image, while a smaller opening (higher f-number) lets in less light for a darker image. This setting also affects depth of field, with a wide aperture producing a shallower depth of field and a small aperture producing a deeper one. White balance adjusts color temperature and doesn’t change brightness. ISO changes sensor sensitivity to light, making the image brighter or darker without changing the actual light amount entering the lens. Shutter speed affects how long the sensor is exposed to light, influencing total exposure over time, but the instantaneous amount of light reaching the sensor is determined by the aperture.