What is the camera aperture and what is it for?

Camera Aperture
Camera Aperture
Camera Aperture

In recent years, whenever smartphones are announced, programmers talk about the characteristics of the camera and almost always the word “aperture” slips between them. Galaxy S9 announcement soon, when we hear this word again.

To put it simply, the camera opening is the opening through which the light passes. In cameras, this hole is in front of the lenses, and the word “aperture” means one of the camera settings. Aperture – one of the three “pillars” of photography, along with ISO and shutter speed. The aperture is important for many reasons – we will talk about them in this article.

Exposure triangle

The three main parameters together are called the exposure triangle. Each of them has a huge impact on image quality. They not only affect the exposure (brightness of the photo), it can be assumed based on their common name.

All three parameters must be balanced so that one cannot be discussed without considering the others. The camera must be able to capture the right moment, accurately transmit light, correctly identify the edges of objects. To do this, adjust the aperture, shutter speed and ISO sensitivity. Consider what each parameter represents.

ISO

ISO is an indicator of the sensitivity of the sensor matrix to light. When photographers used a movie with different ISO values, this exposure setting could not be changed. Modern digital cameras allow you to control the sensitivity of the matrix to light. The photographer adjusts the light intensity, which facilitates the matrix – the result remains equally qualitative.

Theoretically, the lower the ISO value, the less digital noise must be removed during processing after the picture is taken. When the software removes additional pixels, it receives information from nearby pixels – that is, it works almost randomly. The smaller the program    guesses    , the better the picture.

There is no point in using a very low ISO value because the shutter speed and aperture will not be able to adjust it.

Increasing the ISO value increases the sensitivity of the matrix to light – which means you can shoot with less intense light.

It is important for the photographer to remember three things:

  • The lower the ISO value, the lower the light sensitivity of the matrix and vice versa.
  • The higher the sensitivity, the greater the digital noise. The lower the ISO value, the less noise and vice versa.
  • If you can’t enlarge the aperture or reduce the shutter speed, you need to increase the ISO sensitivity – the images will not be blurred.

Shutter speed

This parameter is responsible for how long the shutter stays open when taking a picture or recording a video. When the shutter is open, the light falls on the sensor matrix, so it may not be enough at a high shutter speed – as a result, the exposure will be reduced. The lower the shutter speed, the higher the exposure – and it really depends on how bright the photo will be.

When the shutter is open, the matrix collects all data about what is in the frame. If the subject in the frame is moving, the image is blurred – which is why in most cases a faster shutter results in clearer photos.

  • When you reduce the shutter speed, increase the ISO value or open the aperture to increase the exposure.
  • If you increase the shutter speed, you may need to lower the ISO value or close the aperture to reduce the exposure. Pictures in this case will be less bright.

Every camera has a shutter – even on phones. Film cameras are equipped with a shutter release and closing mechanism, while in digital cameras small matrices simply collect data for a specified time. Therefore, the shutter sound can be turned on or off, although there is actually no mechanical movement. A characteristic sound generated by the program.

Iris

Aperture is an indicator of how open or closed the lens is and is measured in f-feet. The aperture value is the ratio of focal length to the diameter of the aperture in front of the lens. The lower the value, the wider the aperture and more light fall on the matrix.

  • A smaller aperture means more stops – you want to slow down the shutter speed or increase the ISO value to increase the exposure.
  • A wider aperture means fewer stops – you need to set a faster shutter speed or set a lower ISO sensitivity to reduce exposure.

The aperture, like the other two parameters, affects the transparency of the image. Changing different exposure settings affects different image characteristics. After the ISO change, the digital noise increases, the change in the shutter speed increases the degree of blur, changes in the aperture affect the depth of the image.

Portrait

The question may arise: why not aperture the camera minimally to collect all possible light? The fact is that in this case the photos will be too bright and the depth of the image will be quite small.

Image depth is the distance between the closest and furthest objects in focus. The camera can focus on one point only. Everything outside this point is out of focus and blurred.

Summary

Now you know a little more about the aperture and how it affects the quality of photos. Next time, reading the review of the next smartphone, you will understand that the aperture value itself does not matter – it can only be viewed together with other camera parameters.