Which term refers to the size of the lens opening through which light passes?

• A. Aperture
• B. Shutter speed
• C. Iso
• D. White balance

Answer: (A)

Aperture is the size of the lens opening through which light passes. It’s created by the lens diaphragm and is adjustable, described by f-stops like f/2.8 or f/8. A wider opening (smaller f-number) lets more light in and produces a shallower depth of field, while a smaller opening (larger f-number) lets in less light and increases depth of field. This setting works with shutter speed and ISO to determine overall exposure: aperture changes brightness, shutter speed controls how long the sensor is exposed, and ISO changes the sensor’s sensitivity. White balance affects color temperature, not the amount of light entering the lens.