Aperture of the main camera. What are the parameters for choosing a smartphone with a good camera

Greetings, dear readers my blog. We are in touch with you, Timur Mustaev. Yesterday I came across a number of photographs of the so-called "professional" photographer, and one gets the impression that many simply do not understand the aperture of a camera.

Therefore, I decided to write detailed article about this factor, so that people at least understand the main points and how to use it. Are you aware that aperture affects the quality of photos? You wonder how? We will talk about this in this article.

Before continuing to read the article, first read the and. The quality of your photo depends on these parameters.

After reading the material, you will understand the basic principle of the diaphragm, and also learn how to set various parameters for shooting your scenes. Well, is it time to start?

When buying a camera, many immediately start practice without touching on the theoretical part. After some time, the ardor and spirit of photographers becomes weaker and weaker, many leave their "cars" collecting dust on the shelves, because after digging a little in the settings, they get pictures that do not satisfy their ambitions.

To prevent this from happening to you, you must first understand the theory in order to get better quality work, to please yourself and your loved ones, and in the future and partners!

What is a diaphragm?

What is aperture in a camera, a similar question is often asked by beginners in photography, and after a little acquaintance with the aperture device, they immediately start shooting, without understanding the essence and nuances of using the "hole", thereby obtaining very typical photos without plot and zest.

You are probably wondering the "hole" question? And what does she have to do with it? In the vocabulary of photographers, the diaphragm is also called a hole, a hole. So, this is a special mechanism in the form of a ring, consisting of petals, which regulates the transmission of a given volume of light to the camera matrix.

The more the petals are open, the more light hits the matrix, and vice versa, the less the petals are open, the less light is.

For beginners, such a designation of the term may seem very complicated, and in order to understand what it is and how the opening mechanism works, you can simply imagine the eye, namely, the wider the pupil is opened, the more light falls on the retina and vice versa. Light determines the level of exposure.

Principle of operation

After getting acquainted with the mechanism of action, it is necessary to understand how it works, is determined and changed. Anyone who has worked with a camera has come across an f value and a number of numbers, this is the definition of aperture, which can be changed and adjusted to different scenes.

The f-stop is a certain number of numbers with an f value, namely: f / 1.4; f / 2; f / 2.8, etc. Basically, the aperture line ends at f / 22. These numbers indicate how open the petals are in the lens, thereby determining the depth of field and exposure.

The main point is that, what less value, which, by the way, is expressed in numbers, at the diaphragm, the wider the diaphragm. Consequently, it will be maximally open at f / 1.4, and at f / 22, the "hole" will be minimally open. This mechanism of operation applies to all cameras, Nikon, Senon and others.

How aperture affects exposure

Now we come to the question of the effect of the width of the opening of the petals on the exposure. The bottom line is that the wider the open, the brighter the photo will be. Working with light is very important when shooting any kind of scene. If we talk about practice, then, for example, when shooting in a dark room, it is better to open the aperture wider (up to f / 5.6), and when shooting on a clear day outdoors, the aperture should be closed (from f / 8 to f / 16 ), so that there is no so-called "overexposure".

Here you also need to consider what effect you want to achieve. If you want to blur the background, then the hole should be as open as possible, 2.8 or 3.5.

Effect of aperture values ​​on depth of field

Aperture settings change the depth of field, and this is perhaps one of the main things in photography. This designation means a certain area in the picture, which is distinguished by sharpness, or rather, a difficult area, but, one might say, a range of distances.

Aperture and depth of field are interrelated. This connection is based on the parameters of the aperture, namely, if the ring is fully open, f / 1.8, then there can be no talk of great sharpness.

When the aperture is open, the depth of field is very shallow, and the specific subject you are focusing on will be in focus, and the background will be blurry, but this method is also “popular”, for example, when shooting portraits, where attention is focused on the eyes of the model and the background is blurred.

For portraits, it is desirable to use a width from f / 4 to f / 8, with such a "hole" width, the model will be visible in the picture, and at the same time, the background from behind will be slightly pleasantly blurred, which will give a beautiful photo effect.

Aperture value settings

How to choose the right size for shooting? It's pretty simple, the main thing to know is how to set up required values for shooting. So, the aperture (f / 1.8) is suitable for shooting in poorly lit rooms. Such photos should be taken when photographing various miniature objects or if you want to highlight some specific detail, for example, an eye or a button on a shirt.

A width of f / 4 is good for portraits with an average amount of light indoors. The main thing is not to “miss” when shooting with such values, thereby highlighting, for example, the shoulder, and not the desired face of the model.

With a width of f / 5.6, you can safely "click" a model in full height, and at f / 8 it is worth shooting a group of people.

At sunlight it is worth using the f / 16 and f / 22 values ​​as they will perfectly match the landscape.

Today the market of types and manufacturers of cameras is overflowing, these are well-known Canon and Nikon, and others less famous brands like Fujifilm, Pentax and others. It doesn't matter what kind of camera you have, the main thing is to know the basics of photography, choose the right light and understand parameters such as shutter speed, aperture and ISO.

After reading this article, you should clearly understand what aperture is, how to use it and how to control it to capture your own scenes. All that remains is to pick up a camera and start such a wonderful art as photography!

My to you great advice... Shoot as much as possible, practice. Take your camera everywhere with you. And not when do not stop there!

And yet, I would like to recommend you, simply and very useful video course "" or " My first MIRROR". All the subtleties of obtaining are described in great detail on the video quality photography... Why this particular course? It's simple, I got acquainted with many courses on the Internet and not one in terms of quality and volume of information surpassed the course I recommend. And some have misled me altogether.

My first MIRROR- for fans of the SLR camera CANON.

DSLR for Beginner 2.0- for fans of the NIKON SLR camera.

Good luck with your creativity! See you soon, in the vastness of my blog.

All the best to you, Timur Mustaev.

An aperture, or aperture, is a hole that controls the amount of light entering the camera's sensor (or film in film cameras). Aperture is one of three key elements when adjusting exposure (ISO, shutter speed, aperture).

Changing the value or division of the aperture not only allows you to control the amount of "collected" light, but also affects the final image, which you need to understand. Depth of field (DOF) is most important, but it is also possible optical distortion or changes. You need to know how the lens aperture works to make informed decisions about other exposure settings, create creative effects, avoid mistakes, and understand the effect of adjustments on the image.

Steps

Become familiar with basic concepts and terms. This information will help you better understand the article.

• Diaphragm is an adjustable hole in the lens through which light passes and hits the film (or digital matrix). Like a pinhole in a pinhole camera, it blocks light rays except for those that, even without a lens, could form an inverted image when passing through center point to the corresponding point in the opposite direction on the film. Whereas with a lens, the aperture also blocks light rays that travel far from the center, where the lens of the lens less accurately reproduces (usually with different simple spherical surfaces) geometric shapes without sharp focus (usually much more complex aspherical surfaces), resulting in aberrations.
  • Since each camera has an aperture that is usually adjustable (and if not, at least has the edges of the lens that act as aperture), it is the size of the aperture opening that is usually called "aperture".
• Aperture division or just diaphragm is the ratio of the focal length of the lens to the aperture value. This measurement is used because a certain f-number provides the same image brightness, so the same specific shutter speed is required for a certain ISO value (film sensitivity or equivalent matrix light amplification) regardless of the focal length.
• Iris diaphragm is a device that is used in most cameras to shape and adjust the iris. It consists of a series of overlapping thin metal tabs that can pivot towards the center of the hole inside the flat metal ring. It forms a central hole, perfectly flat in the case of a fully open aperture, when the petals move to the sides, and is compressed by the displacement of the petals towards the center of the hole, resulting in a smaller polyhedral hole (which may also have curved edges).
  • If your camera supports interchangeable lenses or is “pseudo-mirror”, then the lenses are equipped with an adjustable iris diaphragm. If you have a compact model or a "soap dish" (especially in the budget segment), instead of an iris diaphragm, the device is probably equipped with a "ND filter". If your camera's mode switch has M, Tv and Av modes, then it is almost certain that the device has a real iris diaphragm (even in the case of small compact models). If the mode dial does not have these settings, the camera may be equipped with both an iris and a ND filter. The only way to find the exact answer is to consult the specifications in the user manual or a detailed professional review (look for reviews of your camera model in search engines and read the available materials). If a ND filter is used, then the fine tuning»Settings, depth of field, or bokeh will be limited by the fixed aperture of the device. PAY ATTENTION to the mode switch: "M" means manual mode("Manual"), which allows you to set the shutter speed and aperture value. "Tv" - shutter priority mode: the shutter speed is set manually, after which the camera automatically selects suitable value diaphragm. “Av” is aperture priority mode: it is set manually (usually to control the desired depth of field), after which the camera selects the appropriate shutter speed.
  • Most single-lens reflex cameras close the iris, after which it can be seen from the front of the lens, only when the function is turned on. preview exposure or depth of field.
• Cover up or darken aperture means using less or (depending on the context) relatively not great importance aperture (large f-number).
• Open aperture means using a larger or (depending on the context) a relatively large aperture value (small f-number).
• Open aperture is the largest aperture (smallest f-number).
• Depth of field of the imaged area is a specific front or back portion of the frame, or (depending on the context) the amount of front or back portion that looks sharp enough. Decreasing the aperture increases the depth of field and decreases the amount of blurring of objects outside the sharp area. Exact value Depth of field is somewhat subjective, as sharpness gradually decreases from the most accurate focal length, and the perceived blur of the image depends on factors such as the type of object, other sources of lack of sharpness and viewing conditions.
  • The relatively large depth of field is called big, and relatively small - small depth of field.
• Aberrations- these are flaws in the ability of the lens to sharply focus light. V general outline, inexpensive and exotic lenses (such as ultra wide angle) will have more noticeable aberrations.
  • Aperture does not affect linear distortion (straight lines appear curved), but they often disappear closer to the center of the zoom range of a zoom lens. You can compose your shot so as not to draw attention to distortion (for example, not to place explicit straight lines such as buildings or the horizon close to the edges of the frame), or automatically correct a flaw in the camera or in subsequent computer processing.
• Diffraction- This is a basic aspect of the behavior of waves that travel through small apertures, which limits the maximum sharpness of all lenses at small apertures. It becomes more noticeable after f / 11, with the result that an excellent camera and lens can produce quite mediocre results (although sometimes they are great for specific tasks like very great depth sharpness or long exposure when low sensitivity or ND filter cannot be used).

1. Depth of field in the imaged area. Formally, depth of field is the range of distances to an object within which objects in the image have acceptable sharpness... There is only one distance at which objects will be in ideal focus, but the sharpness decreases gradually before and after that distance. At shorter distances in each direction, the blurring of objects will be so slight that the size of the film or sensor will not allow blurring to be detected. Even larger distances will not affect the "sufficient" clarity of the final image too much. Depth-of-field markings for specific apertures next to the lens focusing ring allow you to estimate given value. .

   • About a third of the depth of field is before the focal length, and another two-thirds is behind (unless extending to infinity, as this refers to the value at which rays of light reflected from an object must bend to converge at the focal point, and rays that pass through long distances, strive for parallelism).
   • The depth of field decreases gradually. With a small aperture, the background and foreground will appear a little fuzzy or even sharp, while with a wide aperture, they will be very blurry or completely unrecognizable. If foreground and background are important, then they should remain in focus. With a weak blur, the general context is preserved, and it is better to blur the distracting background as much as possible.
     • If you want to blur the background, but the depth of field is not enough for the subject, then focus on the element that will attract the main attention (often the eyes).
   • As a rule, in addition to the aperture, the depth of field also depends on the focal length (the greater the focal length, the smaller the DOF), the frame size (the smaller the film or sensor format, the greater the DOF if the angle of view or equivalent focal length remains the same) and the distance to subject (much smaller at short focal lengths).

     If you need to get a shallow depth of field, you can buy a super fast lens (expensive) or zoom in on the object (free) and open the aperture as much as possible, even with an inexpensive, low aperture lens.

   • From point of view artistic value depth of field is used to sharpen the entire image, or to “de-focus” and blur the foreground or background that distracts from the central subject.
   • From a practical point of view, DOF allows you to set a small aperture and set a "super focal length" (the closest distance at which DOF extends to infinity from a specific distance; refer to the appropriate table or depth of field markings on the lens to select an aperture) or an estimated distance to quickly Take pictures with manual focus, or photograph a subject that moves too quickly or unpredictably for autofocus to work correctly (in this case, a fast shutter speed is also required).
   • It should be remembered that usually all changes in depth of field are subtle in the viewfinder or external screen when building a composition. Modern cameras measure parameters at maximum open aperture lens and cover the aperture to the selected value already at the moment of exposure of the frame. Depth-of-field preview is usually only an approximate and inaccurate result (ignore strange patterns on the screen when focusing, as they will not appear in the final image). What's more, viewfinders on modern DSLRs and other autofocus cameras do not even show true open-aperture depth of field when using lenses above f / 2.8 (it will be even shallower than it looks; rely on autofocus if possible, not on subject). The best option for a digital camera, simply take a photo, view and zoom in on the LCD screen, and determine if you are happy with the sharpness (or degree of blur) of the background.

Interaction of the diaphragm with pulsed light (flash). The flash usually fires so quickly that only the aperture affects the flash component of the exposure (film and digital cameras almost always have a maximum flash-compatible shutter speed for "sync"; at a faster shutter speed, only part of the frame is exposed, due to the peculiarity of the "curtain" shutter ; within special regimes high-speed flash sync uses short-term firing of weak flashes, each of which exposes a different part of the frame; this greatly reduces the range of the flash, so this option is rarely used). The wide aperture increases the flash range. It also expands the effective range of fill-flash by increasing proportional flash exposure and shortening ambient light penetration time. Small aperture prevents overexposure on close-ups due to the lowest power below which it is impossible to weaken the flash (bounce flash, which is not as effective, will be useful in this situation). Many cameras support adjusting the balance of flash and ambient light through the "flash exposure compensation" function. For challenging flash photography, digital cameras are best, as the results of brief flashes of light are not obvious on their own, even though some studio flash models have “modeling flash” and functional portable flashes offer similar preview modes. with modeling backlight.

Find out the optimum sharpness for your lenses. Different lenses differ from each other, and for optimal results, you must shoot with different meaning diaphragm. Take photos of subjects with lots of fine details at different apertures and compare shots to see how lenses behave at different apertures. It is recommended to place the entire object at "infinity" (10 meters or more for wide angle lenses and several tens of meters for telephoto lenses; distant forest stands are usually suitable) so as not to confuse lack of sharpness with aberrations. Here are some tips:

• Nearly all lenses have poor contrast and reduced sharpness at their widest apertures, especially in the corners of the image. This is especially true for digital "point-and-shoot" or inexpensive lenses. Therefore, if you need to provide high detail in the corners of the image, it is better to use a smaller aperture value. Typically f / 8 provides the best sharpness for flat subjects. If objects are located on different distances, an even smaller aperture will provide a deeper depth of field.
• Nearly all lenses result in noticeable vignetting at open apertures... In this case, the edges of the image appear darker than the center of the frame. This effect can be useful for many photographs, especially portraits; he focuses on the central part of the image, which is why many add this effect in post-processing. But it's always best to know what the original shot will look like. Typically above f / 8, vignetting disappears.
• Zoom lenses differ in their focal lengths. Perform the specified checks with at different levels optical approximation.
• The phenomenon of diffraction leads to the fact that pictures with almost any lens become less sharp at f / 16 or less, and especially at f / 22 or less.
• All these aspects make it possible to obtain an image that is optimal in terms of clarity, if a picture has already been built for it. best composition, including depth of field, and unless it is spoiled by camera shake when the shutter speed is not fast enough, or subject blur or noise when “sensitivity” is too high (gain).
• There is no need to waste film on such experiments. Check lenses for digital cameras, read the reviews, and as a last resort, proceed from the facts that more expensive fixed focal length lenses (no zoom) give the best picture at f / 8, less expensive and complete lenses show best result at f / 11, while cheap or exotic lenses such as ultra-wide-angle specimens and models with a wide-angle or telescopic extension lens should be used with an aperture of f / 16 (for extension lenses on digital "soapboxes", set the minimum aperture aperture or use the aperture priority mode in the menu) ...

2. Special effects associated with the diaphragm.

   • Japanese word bokeh often used to describe appearance areas of the image that are out of focus, especially light areas as they appear as drops of light. There is a lot of material out there about these light drops, which can be brighter in the center, sometimes brighter around the edges like donuts, or a combination of both, but usually they only pay attention to this in articles about the bokeh effect. It is important to remember that such blur spots:
     • Will be larger and more diffuse with a wider aperture.
     • Will have soft edges at the widest aperture due to the perfectly circular lens hole (lens edges, not iris petals).
     • Depends on the shape of the opening of the diaphragm when it is not fully open. This effect is most noticeable when the aperture is wide open due to the size of the opening. Bokeh can be considered unattractive in lenses whose aperture is imperfect. round shape(for example, inexpensive 5- or 6-blade aperture lenses).
     • May be crescent-shaped instead of a circle around the edges of the image when the aperture is particularly wide (this may be because one of the lens elements is not large enough to fully illuminate all parts of the image at this aperture, or such light circles expand in a strange way due to "asymmetric aberration ”at a very wide aperture, which usually becomes a problem only when shooting flashlights at night).
     • They are predominantly in the form of rings and bagels in telephoto SLR lenses due to the presence of central interference.
   • Diffractive rays form asterisks... Very bright areas of the image, such as light bulbs at night or small mirror reflections sunlight will be surrounded by "diffractive rays" that form "stars" at a small aperture (the effect arises due to increased diffraction at the vertices of the polyhedral aperture, which is formed by the diaphragm blades). The number of vertices or rays corresponds to the number of aperture blades (with an even number) due to the overlap of opposite rays, or twice their number (with an odd number of blades). Beams are weaker and less pronounced on lenses with very big amount petals (usually old lenses like old Leica models).

3. Take pictures. The most important thing (according to at least, in the context of aperture) - control the depth of field. It's simple: the smaller the aperture, the greater the depth of field; the larger the aperture, the less depth sharpness. Also, a wider aperture blurs the background more. Here are some examples:

   • Cover the aperture for a greater depth of field.
   • Depth of field decreases as you get closer to your subject... So, for macro photography, you can cover the aperture more than for landscape photography... Insects are often photographed at f / 16 or less and illuminate the subject with plenty of artificial light.
   • Open the aperture for shallow depth of field... This method is suitable for portraits (much better than awkward automatic modes). Open the aperture fully, fix the focus on the eyes, adjust the composition: a blurred background will distract less attention from the main subject.

     Remember to use a faster shutter speed for a wide aperture. In bright daylight, make sure the camera is not trying to go beyond the fastest shutter speed (typically 1/4000 for digital SLR cameras). To do this, you need to lower the ISO value.

Take pictures with unusual effects. If you photograph light sources in dark time days with a suitable camera and want to get asterisks, then close the aperture. In the case of large and round bokeh drops (although not always full), use an open aperture.

4. Fuzzy image due to diffraction and (in lesser degree) focus misses (which, in addition to being blurry, create strange patterns) can sometimes be corrected using functions such as "unsharp masking" when processing on a PC. Examples include GIMP and Photoshop. The function will allow you to sharpen the boundaries, although it will not be able to create small details that did not fall into the picture (if too much applied, the transitions will be too sharp and inaccurate).
5. If aperture size is important to your shot and you are using an automatic camera, then Aperture Priority or Program Shift (pre-set aperture and shutter speed pairs for correct exposure in different conditions) will suit you.
6. All lenses have certain distortions: “ideal” lenses cannot be found even among professional models costing tens of thousands of rubles. The good news is that renowned optics manufacturers like Nikon, Canon, Pentax, Zeiss, Leica, Sony / Minolta and Olympus often create “distortion correction” profiles that can be downloaded from the Internet and applied during image processing (for example, in Adobe Photoshop and Adobe Camera RAW). When using good software and lens profiles, you can capture images without barrel or pincushion distortion, which are more pleasing to the eye. In this example with a wide-angle panoramic landscape shot, the problem is that "perspective distortion" and "barrel distortion" bends the trees at the corners of the image toward the center of the image. It is quite obvious that this is lens distortion and it is unlikely that trees would be rounded this way.

Warnings

• Make stars with bright points of light, like street lamps, that are less bright than the sun.
  • Do not point a telephoto lens, especially a super aperture lens or an ultra long focus lens, directly at the sun for stars or any other reason, as there is a risk of damaging your eyesight, shutter, or camera sensor.
  • Do not point cameras without a shutter mirror like the Leica towards the sun (only briefly when shooting handheld and with a small aperture), so as not to burn a hole in the shutter, otherwise repairs will cost you a lump sum.

One of the main useful features of a modern smartphone is the photography function. To receive good photo, it is necessary that the camera has certain qualities and characteristics. Today, within the framework of this article, we will talk about what a camera aperture is, what it is responsible for, and how it affects the quality of images.

Almost every one of us takes at least 2-3 pictures a day using a camera. mobile phone... Someone then posts them on Instagram or Facebook, shares in messengers, posts on message boards. All of us are united by one desire - that the smartphone camera takes better pictures, the photos are clearer, richer, more detailed, so that there is less noise, etc. How can this be achieved? This is influenced by a lot of different factors, characteristics and settings:

• The number of megapixels and their size
• White balance
• Compression quality and image format
• Camera fineness

Today we will just talk about the last characteristic - what is the camera aperture? How does it affect the quality of the photo?

Aperture on a camera is one of three factors that affect exposure. Therefore, understanding the action of the aperture is a prerequisite in order to take deep and expressive, correctly exposed photographs. There are both positive and negative sides use different apertures, and this lesson will teach you what they are and when to use which ones.

Step 1 - What is camera aperture?

The best way to understand what a diaphragm is - to imagine it as the pupil of the eye. The wider the pupil is open, the more light hits the retina.

Exposure is made up of three parameters: aperture, shutter speed, and ISO. The diaphragm diameter adjusts the amount of light entering the sensor depending on the situation. There are various creative options using an aperture, but when it comes to light, it is important to remember that wider holes let in more light and narrower ones less.

Step 2 - How is aperture determined and modified?

The aperture is determined using a so-called aperture scale. On the display of your camera, you can see the F / number. The number indicates how wide the aperture is, which in turn determines exposure and depth of field. The lower the number, the wider the hole. This can be confusing at first - why does a small number correspond to a larger aperture? The answer is simple and mathematical, but first you have to know what aperture series or standard aperture scale is.

Diaphragm row:f / 1.4,f / 2,f / 2.8,f / 4,f / 5.6,f / 8,f / 11,f / 16,f / 22

The main thing you need to know about these numbers is that there is one exposure stop between these values, that is, when you move from a lower value to a higher one, half the light will enter the lens. V modern cameras there are also intermediate apertures that allow you to fine-tune the exposure. The tuning step in this case is ½ or 1/3 step. For example, between f / 2.8 and f / 4, there will be f / 3.2 and f / 3.5.

Now about more complicated things. More precisely, why the amount of light between the main aperture values ​​is two times different.

It comes from mathematical formulas. For example, we have a 50 mm lens with an aperture of 2. To find the aperture diameter, we have to divide 50 by 2. This is 25 mm. The radius will be 12.5 mm. Formula for area S = Pi x R 2.

Here are some examples:

50mm lens with f / 2 = 25mm aperture. The radius is 12.5 mm. The area according to the formula is 490 mm 2. Now let's calculate for f / 2.8 aperture. The diaphragm diameter is 17.9 mm, the radius is 8.95 mm, the opening area is 251.6 mm 2.

If you divide 490 by 251, you get not exactly two, but this is only because the aperture numbers are rounded to the first decimal place. In fact, the equality will be exact.

This is how the ratios of the aperture openings look real.

Step 3 - How Does Aperture Affect Exposure?

As the aperture size changes, the exposure also changes. The wider the aperture, the more the matrix is ​​exposed, the brighter the image is obtained. The best way to demonstrate this is to show a series of photographs where only the aperture changes and the rest of the parameters remain unchanged.

All the images below were taken at ISO 200, shutter speed 1/400 sec, no flash, and only the aperture was changed. Aperture values: f / 2, f / 2.8, f / 4, f / 5.6, f / 8, f / 11, f / 16, f / 22.

However, the main property of aperture is not exposure control, but change in depth of field.

Step 4 - depth of field effect

Depth of field is a broad topic in and of itself. It takes several dozen pages to reveal it, but for now we will look at it very briefly. It is the distance that will be transmitted sharply in front and behind the subject.

All you really need to know in terms of the relationship between aperture and depth of field is that the wider the aperture (f / 1.4), the shallower the depth of field, and the narrower the aperture (f / 22), the larger the field of field. Before I show you a selection of photos taken at different apertures, take a look at the diagram below. It helps to understand why this is happening. If you don't understand exactly how it works, it's okay, as long as it's important for you to know about the effect itself.

The image below is a photo taken at f / 1.4. It has a pronounced depth of field effect (Depth of Field)

Finally, a selection of photos taken in aperture priority, so the exposure remains constant and only the aperture changes. The f-stop is the same as in the previous slideshow. Notice how the depth of field changes as the aperture changes.

Step 5 - How to use different apertures?

First of all, remember that there are no rules in photography, there are guidelines, including when it comes to choosing aperture. It all depends on whether you want to apply an artistic technique or capture the scene as accurately as possible. To make it easier to make a decision, here are some of the most commonly used aperture values ​​traditionally.

f / 1.4: great for low light shooting, but be careful, there is very little depth of field at this value. Best for small objects or to create a soft focus effect

f / 2: The usage is the same, but a lens with this aperture can cost one third of that of a lens with an aperture of 1.4

f / 2.8: Also good for low light conditions. It is best used for portraits, as the depth of field is greater and will cover the entire face, not just the eyes. Good zoom lenses tend to have this aperture value.

f / 4: This is the minimum aperture used to photograph a person in sufficient light. Aperture can limit autofocus performance, so you run the risk of overshooting when aperture is open.

f / 5.6: Good for 2 person photography, but for low light it is better to use flash light.

f / 8: Is used for large groups as it guarantees a sufficient depth of field.

f / 11: At this value, most lenses have maximum sharpness, so it's good for portraits.

f / 16: Good value when shooting in bright sunlight. Great depth sharpness.

f / 22: Suitable for shooting landscapes where attention to detail in the foreground is not required.

When choosing a smartphone with a good camera, you need to pay attention to its numerous parameters. With the resolution, everything is simple: the more megapixels, the better the theoretical maximum image detail. With the dimensions of the matrix and individual pixels, everything is also simple: the larger they are, the more light it captures, and the higher the clarity will be in a lack of lighting. But the aperture or aperture is a characteristic that is more difficult to understand. For example, the fact that a lower figure is often better is perplexing to many.

Aperture (aperture) is a hole in a camera lens through which light enters the sensor. In the description of smartphones, these words are used interchangeably, but they have slightly different origins. The term “aperture” originally referred to the physical part of the lens, the shutter, which controls the size of the light passage. And "aperture" is a characteristic indicating the characteristics of this shutter.

DSLR lens with variable aperture

Since this detail is absent in mobile cameras, both terms are used in the second sense. Also, the word “aperture” is often used as a synonym for the terms “aperture” and “aperture”. In the description of smartphone cameras, all these concepts characterize the ability of optics to transmit light.

How is the aperture (aperture) of a smartphone camera measured?

The aperture (aperture) value of the smartphone camera is relative value, expressed in terms of the focal length.

The focal length is the distance between the sensor and the optical center of the lens, that is, the point at which light rays converge, falling through the lens into the camera module. The aperture value allows you to determine how effectively the camera captures light in comparison with others.

Smartphone camera aperture location

The numerical value of the aperture is a derived value that indicates the relationship between the FFR (physical focal length) and the diameter of the hole in the lens. It is written in the format of the fraction f / X, where f is the FFR, and X is the divisor. The popular aperture value of f / 2 means that the diameter of the camera opening is half the focal length. If the FFR is 4 mm (this is also one of popular values, since more to get from the module, about 6 mm high, will not work), then with an aperture of f / 2 the diameter of the lens eye will be 2 mm. If the focal length is 5.6 mm, and the aperture is f / 2.8 (such parameters were 12 years ago for the Nokia N73 cameraphone), then 5.6 / 2.8 = 2, that is, the "pupil" has a diameter of 2 millimeter.

Different aperture values. Hole diameters are drawn to the same scale.

What does the aperture value affect?

Since the f-number indicates the diameter of the lens aperture, the amount of light entering the matrix depends on its value. The larger the hole, the more light there will be. Precisely because the number after the fraction is a divisor, the smaller it is, the larger the physical diameter of the "pupil" will be. After all, if you divide 4 by 1.8 (f / 1.8), then we get 2.22 mm, and dividing 4 by 2.2 (f / 2.2) will already give 1.82 mm.

If you recall the formula for the area of ​​a circle πr 2 (and r is half the diameter) and calculate, you can determine the difference in light transmission. For a hole with a diameter of 2.22 mm, the area will be 3.48 mm2, and for 1.82 mm - 2.85 mm2. Dividing the first by the second, we get a difference of 1.22 times, that is, optics with an aperture of f / 1.8 let in 22% more light than with f / 2.2.

Due to the fact that different cameras have different FFRs (for a smartphone it is several millimeters, and for a DSLR it is 10-100 times more), it is impossible to compare very different cameras in terms of aperture. For example, a smartphone with a 1/3 "matrix at f / 2 captures the same amount of light as a full-frame DSLR with an f / 13-f / 15 aperture. and, on the example of which the calculations were carried out above), then the difference in the luminosity makes it possible to estimate the difference in the light transmittance.