What is the aperture of a lens?
Aperture is a hole through which light passes in your camera lens to reach the camera sensor. It works like the “pupil” of an eye, expanding or contracting to modify the amount of light passing through.
This allows you to control the amount of light reaching the sensor, making the photo brighter or darker!
How is it measured?
For a beginner photographer, it can become confusing when numbers come into play.
Aperture appears in the form of f/number, and just like with shutter speed on your camera, you are likely to see only the denominator. This can be confusing because a value of “f/1.8” will be displayed as 1.8 and refers to a large aperture, while “f/22” displayed as 22 indicates a very small one.
This is something you really need to pay attention to: small numbers = large apertures. Large numbers = small apertures.
Minimum and maximum aperture of a lens
Every lens has a limit when it comes to aperture size. If you look at the specifications of your lens, they should indicate what the maximum and minimum apertures are. The maximum aperture is more significant because it indicates the amount of light the lens can capture when it is wide open. A lens with a maximum aperture of f/1.4 or f/1.8 is considered a “fast” lens, while one with a maximum value of f/5.6 is called a “slow” lens.
The minimum aperture is not as important because almost all modern lenses can provide at least f/16 as a minimum. You will rarely need anything smaller than that for everyday photography.
The maximum aperture of a lens is so important that it is included in the lens name itself. The aperture of your diaphragm depends on the brightness of the environment in which you are photographing and the style of photography you are aiming for.
At night, there is a good chance you will use the maximum aperture of your lens to allow maximum light to reach the sensor, especially if you are shooting handheld and need to use a higher shutter speed.
As mentioned, aperture is just one parameter of exposure, and you will need to familiarize yourself with the different settings to understand their interdependence.
Indeed, a photo that is too bright or too dark at the chosen aperture can be adjusted using the other parameters, such as your shutter speed or ISO.