What is the term for the light gathering ability of a camera lens?

The term for the light gathering ability of a camera lens is known as aperture, often expressed in terms of f-stop values. The aperture is an opening within the lens that controls how much light enters the camera when a photograph is taken. A lower f-stop number indicates a wider aperture, allowing more light to reach the camera's sensor, which is essential for capturing images in low-light conditions. Conversely, a higher f-stop number signifies a narrower aperture, reducing the amount of light that can enter.

Understanding aperture is crucial for photographers as it not only affects exposure but also influences depth of field, which determines how much of the image is in focus. This relationship between aperture, exposure, and depth of field highlights the importance of aperture settings in achieving the desired artistic effect in photography.