What is the diaphragm in the camera?

In order to master all the subtleties of photography, as well as achieve mastery, it is necessary to study the basics and principles of work, to understand the capabilities of the camera. The main basis that affects the achievement of a professional level of photography is understanding and the ability to build the exposure of the frame. Exposure is formed from the following components: aperture, sensitivity and shutter speed. It is about the diaphragm, and more specifically about what affects aperture in the camera and how to work with her correctly.

How to get a good, high-quality and professional staff? Any image needs a certain amount of light, in other words, exposure. The camera provides several options for metering light, namely shutter speed, aperture, and sensitivity. Sensitivity - an indicator that changes in the absence of the ability to change the aperture and shutter speed. In addition to the function of regulating the luminous flux, the aperture and shutter speed serve as artistic attributes that allow you to transform photos. In order to skillfully use them and create amazing effects on the photo, you need to understand how they are used, at first it is not easy, but with practice this process becomes automatic.

In addition to the function of regulating the luminous flux, the aperture and shutter speed serve as artistic attributes that allow you to transform photos

What is the diaphragm in the camera?

The diaphragm is translated from Greek as a partition; in English, the term “aperture” is used. This is a special element that is located in the camera’s lens and, if necessary, changes the diameter of the hole through which the light flux enters the photosensitive element (matrix or film). To facilitate understanding of the term and the principle of its operation, we can draw an analogy with an ordinary window: more light enters the room through the window when the shutters of this window are more widely open.

It is accepted to designate the aperture f / 2, f: 2 or F / 2, and is defined as the ratio of the diameter of the relative aperture to the focal length. It is important not to confuse when the open aperture is indicated, and in which cases the focal number, for example f / 16. The aperture is more open when the number after the letter is smaller. Changing the exponent f by one step, the amount of light entering the matrix changes twice, this process is called the exposure level. All changes are made with a fixed step equal to one step. To increase accuracy, the step can be divided into three parts, if necessary.

Examples of possible aperture values

It is difficult to underestimate the importance of the diaphragm capabilities in the camera. She also acts as a tool for photography. The larger the relative opening, the smaller the depth of field will be. With a small depth of field, the main focus object is visually more emphasized, and the background is blurred. In order to achieve a large index of depth of field it is necessary to close the hole as much as possible.

It is also worth considering that working at extreme aperture indicators entails some negative points. With maximum openness, sharpness deteriorates significantly, and with minimum, all dust accumulated on the matrix will be displayed on the frame.

What indicators are affected by the aperture in the camera:

• DOF, smaller when the relative opening is larger;
• Brightness, the more the hole is closed, the less the matrix is ​​illuminated;
• Quality, with the opening as wide as possible, aberrations can occur, and with the maximum closed, diffraction of light may appear. Each of the extremes negatively affects the photo, so it is customary to use average indicators to achieve maximum image quality.

Now it’s clear what is needed and how the diaphragm works. A special shape of the partitions, the so-called petals, is responsible for changing the diameter, the better and more professional the lens, the greater the number of curtains. A good example of photographs with varying degrees of openness:

When closed: the entire frame is in focus and objects are clearly visible.
When open: only the contents of the cup are in focus, and all other objects are blurred as a background

The degree of influence on the boke

First you need to understand the concept of "bokeh". This is a certain fuzziness, blur. Basically, this term is used to describe the blurry background in a photograph. The fact that the diaphragm affects the bokeh has already been mentioned, but that's not all. Not only the value of the relative aperture, but also the shape, as well as other parameters, also affect the bokeh. Examples of shapes created by petals:

Today, manufacturers follow the trends and basically create a round shape, but in some photos the influence of the shape on the bokeh still remains.

How does aperture affect depth of field

When focusing on a specific object, it becomes as sharp as possible with respect to other objects in the frame. But the sharpness of the object and the space behind it depends directly on the relative aperture. In order to simplify understanding, examples of photographs that were shot with different aperture and shutter speeds are offered.

The pictures clearly demonstrate the effect on the sharpness of changes in the diameter of the relative aperture

How to choose and how to control aperture values?

When setting up and selecting the desired aperture value, it is important not to forget that there are no established canons and rules, the selection is made solely on the basis of the photographer’s vision and the goals pursued. The main aperture values ​​are as follows:

• f / 1.4. It is optimal to use for photography in low light, but when you select this value, the depth of field will be minimal. This indicator is great for shooting small objects or, if necessary, create a "soft focus";
• f / 1.2. It is used in almost the same way as the previous one, but at the same time, the cost of a lens with such an aperture is much more democratic;
• f / 2.8. Used when photographing in low light conditions, great for portraiture, as the necessary depth of field gets on the face;
• f / 4. The minimum mode of the relative aperture at which photographing of people in normal lighting conditions is possible;
• f / 5.6. Suitable for taking pictures of several people or objects, but in conditions of insufficient or poor lighting, the use of a flash is required;
• f / 8. It is actively used if it is necessary to take a picture with a large number of important objects or people, this value provides a good depth of field;
• f / 11. The maximum sharpness provided by this mode makes this aperture value optimal when shooting portraits;
• f / 16. It is characterized by a large depth of field and is ideal when photographing in bright light;
• f / 22. The optimal value for photographing landscapes and creating frames in which there is no need to highlight objects in the foreground.

How to properly configure the aperture

There is no universal aperture value, as this indicator is selected depending on many different conditions. However, if you follow the tips and tune-up rules, you can achieve excellent shots under any conditions.

• Average aperture values ​​will achieve optimal image sharpness. In turn, large values ​​make the image more saturated and bright;
• Completely open relative aperture provides better bokeh;
• If photographing is carried out at night, the shutter speed should be increased, and the aperture should be clamped as much as possible;
• An open relative aperture is great for indoor portraiture. If portraits are shot against the backdrop of nature, it is best to set the average aperture or closed. If you want to create an emphasis not only on the main object, but also on the background, then it is better to use a closed aperture;
• If the city landscape is taken, then it is optimal to use the values ​​f / 11 or f / 16;
• The f / 16 value provides a greater depth of field under conditions of shooting a natural landscape; if the image does not correspond to the desired one, you can change the value to f / 11 or f / 8

Thus, the desired aperture value of the camera is selected directly during photography. This value is set in manual mode, automatic or depending on the shooting mode.

To set the desired value in manual mode, you must use the Av (aperture priority) or M (manual setting) mode. This setting method allows you to control bokeh and depth of field, vignetting and other details that affect the future image. In order to correctly change the values ​​of the relative aperture for each individual model, it is necessary to familiarize yourself with the instructions that are attached to the model. Manufacturers have different approaches to setting aperture values.

Having figured out how the diaphragm works, when and how to change its values ​​correctly, you can safely experiment with photography, create high-quality shots, and also achieve mastery and professionalism in the art of photography. With the acquisition of experience, you can use various lenses and get even more interesting shots.