What is the definition of aperture in photography? and What is the meaning of the letter f in cameras?
Definition of aperture
The aperture is a component of the exposure triangle that consists of aperture, ISO and shutter speed.
Aperture is an aperture inside the lens that can be resized to control the amount of light we need in order to get the right exposure for our photos.
The aperture is denoted by the letter f. The letter f appears with a number next to it, eg (f / 1.8). This number simply symbolizes the aperture cavity.
The relationship of the number f to the aperture of the lens is an inverse relationship, meaning the larger the f number, the smaller the aperture and the smaller it is, the greater the aperture of the lens, meaning that f / 1.4 refers to a wide aperture and f / 22 refers to a narrow lens aperture.
The aperture changes from one lens to another, as each lens has a maximum and minimum aperture, but the maximum is the most important, in the case of lenses with a fixed focal length, this maximum aperture value remains constant without changing, unlike the zoom lenses, whose maximum aperture value changes according to the specified focal length Or remain static.
We’ll explain the image above:
14-42mm 1: 3,5-5.6 means that the focal length of the lens varies from 14mm to 42mm, at the minimum focal length value of 14mm, the maximum aperture is f / 3.5 and at the maximum focal length which is 42mm. The maximum aperture is f /5.6 and between them, i.e. 30 mm, for example, up to f / 5.
16-45mm 1: 4 means that the lens has a focal length of between 16mm and 45mm and that in all cases the maximum aperture of the lens is 4.
What is the aperture mission?
The task of the aperture is to determine the depth of field through which we can focus on a specific subject or a complete scene, the larger the aperture of the lens, the smaller the depth of field, and thus isolating the background, so it is recommended to use a large aperture when photographing portraits. As for when the aperture is small, i.e. the number f is large (such as f / 16 or f / 22), then the depth of field becomes larger and we can focus on the whole scene, so it is recommended to use a small aperture when photographing nature.
How do I control the aperture?
The aperture can be controlled while the camera is in manual M or semi-manual AV mode.
When the camera is in manual mode M and we want to change the aperture value, we look for a button bearing the word AV, press it, and at the same time we move the selection wheel. When using the AV mode, it is sufficient to move the selection wheel.
