Aperture is the central part of the lens, a hole of variable size. The smaller the width, the greater the depth of field (depth of field). It is denoted by numbers from the series:
In expensive cameras, you can choose other intermediate values. High depth is needed for high-quality landscape shots, where you need to get a sharp foreground and background. To do this, set the aperture to 8 mm or more.
Small depth of field is needed in order to draw a person’s attention to the central object of the photo, blurring unnecessary objects. To blur the background, you need to set the aperture to 2.8 mm.
Large lenses of 18-55mm greatly limit the creative possibilities of people, because at a focal length of 55mm it will not be possible to put more than 5.6 DOF.
To control the lens, you need to switch the control dial to aperture priority mode (AV or A). In this case, you choose with which aperture you want to take pictures, and the device selects all other parameters by itself. In aperture priority mode, the exposure compensation function is still available.
Aperture has the opposite effect on the level of exposure – the larger its size, the darker the picture (a pinched pupil transmits less light than an open one).