Camera Trivia 🦍 "Aperture Edition"

This week we're talking about the last element of the exposure triangle - aperture.
(If you want to know the differences between different apertures, you can skip directly to the last image.)

What exactly is aperture?

The f-value of an aperture indicates the maximum aperture value of each lens. The closer the number is to 0, the greater the light intake will be, and the shallower the depth of field will be at the same focal length. The aperture is a component placed at the rear of the lens, used to directly limit the amount of light passing through the lens. The aperture blades that make up the aperture vary in number depending on the lens design. Lenses with more aperture blades can produce rounder bokeh and more distinct sunstars. Usually, more expensive lenses have more aperture blades.

Aperture numbers help us quantify the light intake of each lens. Theoretically, with the same camera settings, different lenses can produce photos with an identical exposure level. However, this is just an ideal situation; I will elaborate on this below.

Like ISO and shutter speed, aperture is also expressed in "stops." Similarly, each stop difference doubles the light intake. Since the area of the light-gathering circle determines the light intake, you'll see that each aperture stop differs by the square root of 2, which is approximately 1.41 times. Below are the values for each aperture stop:
f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16

Is f/ the only type of aperture value?
Besides f/, there's another measurement called T-stop. Simply put, f-value is the ideal/theoretical value, while T-value is the practical value.
This is why you might find that when you and a friend are using the same aperture to shoot, the brightness always seems to be different. It's because lenses with the same f-value can have different light transmission rates due to varying glass elements, resulting in the same f-value but different T-values.

For the captioned photos, please refer to instagram post