Aperture defines the size of the opening in the lens that determines how much light will be falling onto the sensor or film.
Aperture is important because it affects exposure and depth of field.
Maximum Aperture Means
The “maximum aperture” of a lens is also called the “Lens speed”. A lens with a large maximum aperture (e.g. f/2) is called a “fast” lens where as f/4 will be slower than the f/2. Large aperture allows us to use high (fast) shutter speeds and still receive sufficient exposure. Such lenses are ideal to shoot moving subjects in low light conditions.
1. We can conclude that with larger aperture the quality of digital camera to perform in low-light situations will be increased, since a larger lens opening allows more light than a smaller lens opening.
2. A larger maximum aperture allows us to use faster shutter speed as well.