What are photos in photography

Tripod: Gitzo GT2531 Mountaineer+.
Manfrotto 468MGRC2

The principle of exposure equivalence

The camera is an amazing tool. It's amazing how with a click of the shutter button you can freeze the present moment and save it for the future. The way the camera works seems pretty simple, but when you press the shutter button, a lot happens. To get the right exposure, you need to choose the right combination of aperture, shutter speed, and ISO that form the exposure triangle.

Put simply, the principle of equivalent exposure means that you get the same (or equivalent) when using different aperture, shutter speed and ISO values. There are many combinations of these three parameters that can be used to achieve equivalent exposure. This is the perfect complement to the Tamba rule (or also known as the 'f/16 rule' or 'sunny 16').

To better understand the subject, let's recall the basic principles of the camera and exposure. If you already know all this, you can scroll down to the last section, which describes the principle of exposure equivalence itself.

How does a camera take pictures?

There are all kinds of cameras – DSLRs, mirrorless cameras, film cameras and cell phone cameras. Even if the technique they use is different, the basic principle is always the same. DSLR cameras are most specific in that they have a mirror that allows the use of an optical viewfinder. For all others, the procedure is similar.

The basis of every camera is the image sensor (or the film in analog cameras). It creates the image.

Light reflected from an object is passed through an aperture (cover), hits the image sensor, which has a certain sensitivity (ISO) and is given a fixed time (exposure time). This is more or less what the photo looks like when the shutter button is pressed. These three pieces of information—aperture, shutter speed, and ISO—are the components of the exposure triangle.

Most cameras allow you to manually set the aperture value for each of these three metrics. A photo is considered well exposed when it is bright enough and does not contain areas that are clipped (This means that no pixel of the image is completely black or white. The histogram shows them at the edges). The most commonly used exposure settings are listed in the table below (of course the list is not exhaustive).

Typical values for aperture, exposure time and ISO

cover

The aperture is the variable-diameter opening in the lens that allows light to enter the sensor or film directly. The principle of the iris is similar to that of the human pupil: the wider it is open, the more light reaches the retina. It also works the other way around: to reduce the amount of light, for example on a bright sunny day, the pupil is visibly narrowed.

The aperture setting is called a degree. Here is a typical example of a lens' f-stops.

f/1.4 - f/2 - f/2.8 - f/4 - f/5.6 - f/8 - f/11 - f/16 - f/22

The smallest number corresponds to the largest open aperture and the greatest amount of light transmitted. With each additional step, the amount of light that lets through is reduced by exactly half. For example, the amount of light that the camera sensor receives at an aperture of f/2.8 is four times less than at an aperture of f/1.4. The exposure is controlled by the aperture.

In addition to controlling the amount of light that enters, the aperture is responsible for another important aspect of photography - depth of field.

The aperture is f/2.8. The rear and front background are clearly out of focus.

The aperture is f/8.0. The depth of field is much greater than in the previous image.

Depth of field determines how much the foreground and background are blurred in relation to the subject that is in focus. If you take a photo with an open aperture, the out-of-focus objects will blur a lot. This is called shallow depth of field. On the other hand, if you shoot with the aperture closed, the displayed depth of field will be significantly larger.

Controlling depth of field is important in various areas of photography. If you're shooting landscapes or interiors, you probably want to keep the whole picture in focus.

exposure time

The shutter speed (or exposure time) determines how long the light stays on the camera sensor or film.

The camera's shutter opens only for the exposure time, allowing light to fall on the sensor for a precisely defined period of time. The longer the exposure time, the brighter the photo.

Setting the exposure time works in a similar way to setting the aperture. With each additional exposure, the amount of light received is reduced by exactly half.

In a 1/4 second, the camera's sensor receives only half the amount of light that it would have received with a 1/2 second exposure time (with the same shutter speed and aperture setting).

Fast shutter speeds allow us to 'freeze' the image, while slow shutter speeds blur moving subjects.

This photo was taken with an exposure time of 1/1250 second. With such a fast shutter speed, we can freeze the rapid flow of water and see individual water splashes.

And this was captured at a shutter speed of 1/3 of a second. The water looks very different here.

If you want to get a clear picture of something very fast, you should always take the picture with a fast shutter speed.

Composition errors - are they acceptable?

Many classic mistakes today can be called a modern look, the author's idea. We already talked about this in the article about marriage in photos. For example, celebrity cropped tops have now become the norm on the pages of glossy magazines.

However, we do not recommend cutting off any parts of the body, not distorting the horizon and observing the rules of composition. This is especially important for beginners. It helps them understand the basics and know how to compose things. And when you already know how to do things right and well, there's always room for experimentation!

degrees and aperture

The aperture is indicated by a number preceded by the letter f, sometimes called 'f-stop', which indicates the diameter of the aperture. The smaller the number after f, the larger the diameter of the aperture and the more light reaches the sensor; the larger the number after f, the smaller the aperture and the less light reaches the camera.

With the aperture, the f-number is doubled or halved by a whole stop. In this case, the factor is 1.41 (the square root of two). For example, changing the f-number from f/2.8 to f/4 corresponds to decreasing the exposure by one stop, since 4 = 2.8*1.41. Changing the f-number from f/16 to f/11 increases the exposure by one stop since 11 = 16/1.41.

As with shutter speed, the f-stop is 1/3 stop on most cameras.

Equivalence of aperture values

The aperture values allow a direct comparison between shutter speed, aperture and ISO. This means you can easily change these three parameters while keeping the exposure the same.

Here's an example. Let's say you take a picture with a shutter speed of 1/60s, an aperture of f/8 and an ISO sensitivity of 200. However, you notice that the subject is a little out of focus at this shutter speed, so you decide to reduce the shutter speed to 1/120 s.

If you set the shutter speed one step faster, you will get a darker photo because only half as much light will hit the sensor. To compensate for this reduction, you now have to increase the exposure by 1 stop, at the expense of another property. If you know how to change aperture values, it's easy.

You can e.g. For example, open the aperture wider to let in more light - set it to f/5.6 instead of f/8 - increasing the exposure by one stop and actually going back to the original option. Alternatively, you could increase the ISO to ISO 400, which would also increase the exposure by one notch.

It's easy to see that the stopwatch is an easy way to set and adjust exposure.

cover

The aperture setting determines the size of the lens opening through which light enters the camera. Most lenses have an adjustable aperture - the size of the aperture is indicated by the f-number (the relative aperture of the lens) or f-stops, as they are also known. The f-number of most portrait lenses ranges from f/1.4 to f/22, but can be higher or lower. The smaller the f-number, the larger the aperture and vice versa. An aperture of f/22 is a small aperture that lets a minimum of light into the frame, while f/2.8 is a relatively open aperture that lets in more light. The basic trick to taking photos is to balance the ISO, shutter speed, and amount of light that lets through the aperture so that the photo is well exposed—neither too dark nor too light.

However, the aperture has another function that is particularly important for portraits. The size of the aperture determines the depth of field (DOF), or simply depth of field, which is how much of the photo, from background to foreground, is in focus. An image with a large depth of field is in focus from the foreground to the background, while an image with a shallow depth of field is only in focus at a specific point in the image.

Portrait with shallow depth of field (left) and Portrait with shallow depth of field (right).

Adjusting the aperture to get the image you want is extremely important for portraits. When shooting portraits in an environment where the background and space around the subject are important for understanding their character (or e.g. their profession), it is recommended to use an aperture setting of at least f/5.6, to keep most elements of the composition in focus.

If you want the subject's eyes to be in focus and the rest softly blurred (for a bokeh effect), set the aperture to f/2.8 or lower if the lens allows. To keep things as simple as possible, an open aperture is generally considered a setting conducive to beautiful portraits.

lenses

Some lenses are commonly referred to as 'portrait lenses' because they are best suited for the task, but as with cameras, many great portraits have been captured with other types of lenses, from wide-angle to telephoto. Of course, portrait lenses can be used for more than just portraits.

Focal length is the most common way to describe and classify lenses. Long focal length lenses are those with focal lengths between 85mm and 600mm (telephoto/telephoto). Lenses with short focal lengths from 8mm (Fichai) to 35mm are called wide-angle lenses. The range in between, from 40mm to 70mm, is usually referred to as the normal focal length (although there is disagreement about the definition). Both regular and telephoto lenses, especially those between 85mm and 105mm, are commonly used for portraits. Whether you use a zoom lens with different focal lengths or a prime lens, these are considered the optimal focal lengths for face and portrait photography.

Canon EF 50mm f/1.4 USM

A major reason wide-angle lenses aren't great for portraits is that they create distortions that your subject won't like: the nose appears too big, the eyes are wide, and the overall shape of the face can look odd, especially if it's from the page is recorded. That's not to say you can't take portraits with such distortion - it can even help capture the character, but it's the exception rather than the rule.

With long telephoto lenses, on the other hand, the image section is compressed so that the background and foreground are unnaturally close together. This has its advantages for portrait photographers, but one should not overdo it with this effect. Another reason to avoid long telephoto lenses is purely practical. If you're not far enough away, you won't be able to focus or even get everything you need in the frame.

#3 Angelok

• Group: Users
• Messages: 679
• Registration: 17-May 09
• Gender Male
• Camera: Nikon D90
• Optics: AF-S DX NIKKOR 18 – 105mm VR
  Tamron AF 70-300mm f/4.0-5.6 Di LD Macro 1:2
  Nikon 18-55mm f/3.5-5.6G ED AF-S DX

You need to memorize this series of standard numbers like a multiplication table: 1/0.7; 1/1; 1/1.4; 1/2; 1/2.8; 1/4; 1/5.6; 1/8; 1/11; 1/16; 1/22; 1/32; 1/45; 1/64
The difference between adjacent numbers is one stop. The aperture range changes by a factor of 2.
At f/2.8, 'close one degree' means set f/4.

I should add that the phrase 'one stop' does not just refer to the aperture.
'One stop' simply means 'by a factor of two':
– For the shutter speed – we multiply by 2.
- For ISO - divide by 2.
– For the aperture – we multiply by the square root of 2

message changed: LAY (06 July 2010 – 12:13 p.m.)

#5 AL_341

I have tried more than once in the forum to clarify this terminological question for myself. Apart from more confusion and irritation on the part of the explainers, nothing good has been achieved so far.
I'll try to figure this out.
Everything is clear about the reference principle, but the question of TERMINOLOGY is still open. For some reason the answer satisfies the question's author (the nekster said one thing in his own words and the scale given is quite another), but not me.

A change in exposure by a factor of 2 is 1 stop. That's called a STOP!!! Assumed.
necster quoted a 'standard scale series' where STOP consists of TWO scale levels for some reason. What this 'norm' is, since it has a stop of two semitones, is unclear. But let's assume that she is too. But then the question arises: What are these half steps called?
In recent years, all such scales in instruments have been divided into THREE. This raises a similar question: What are these THREE steps called?
Some call it 'one click', some 'a third step', some 'step', some insist on calling it that. STOP and insist.
There is no ambiguity in literature either, especially not now. So how can you call it RIGHT, gentlemen photographers with many, many, many years of experience? I don't want to be joking.

But the most nerve-wracking question for all gurus is this: If STOP is a change in exposure by a factor of 2, then what do we call STEP.

I personally (and therefore don't insist) call a change in exposure by a factor of 2 a step and a third of a step a STEP. But what is the right way after photoscience. The most important thing in photo technology, the basics, and such a jumble of terms.
I would appreciate if someone could give me the correct name in English, like Nikon. Otherwise, you're wondering that too -- and that's where the fun begins of mixing up the sound of the words stop/stop/step.

feet and bezel

The aperture is indicated by a number preceded by the letter f, sometimes called 'f-stop', which indicates the diameter of the aperture. The smaller the number after f, the larger the diameter of the aperture and the more light reaches the sensor; the larger the number after f, the smaller the aperture and the less light reaches the camera.

With the aperture, the f-number is doubled or halved by a whole stop. In this case, the factor is 1.41 (the square root of two). For example, changing the f-number from f/2.8 to f/4 corresponds to decreasing the exposure by one stop, since 4 = 2.8*1.41. Changing the f-number from f/16 to f/11 increases the exposure by one stop since 11 = 16/1.41.

As with shutter speed, the f-stop is 1/3 stop on most cameras.

Equivalence of f-stops

The feet give us a direct comparison between shutter speed, aperture and ISO. This means you can easily change these three parameters while keeping the exposure the same.

Here's an example. Let's say you take a picture with a shutter speed of 1/60s, an aperture of f/8 and an ISO value of 200. However, you find that the subject is out of focus at this shutter speed, so you decide to take the reduce shutter speed to 1/120 s.

If you set the shutter speed one step faster, you will get a darker photo because only half as much light hits the sensor. To compensate for this reduction, you now have to increase the exposure by 1 stop, at the expense of another property. Now that you know how to change aperture values, it's easy to do.

For example, you could open the aperture wider to let in more light—that is, set it to f/5.6 instead of f/8—thus increasing the exposure by one degree and essentially going back to the original option. You could also increase the ISO number to ISO 400, which would also increase the exposure by one notch.

It's easy to see that the stopwatch is an easy way to set and adjust exposure.

Special considerations when setting exposure

When changing the three exposure settings, it's important to remember that each change has different effects.

exposure time. A relatively slow shutter speed can result in a blurry photo, either due to camera shake during capture or due to the movement of the subject itself.

Cover. A large aperture creates a shallow depth of field, and some subjects in the composition may not be sharp. On the other hand, a shallow depth of field isolates the subject. Therefore, if you want to achieve this effect, you should not use small apertures (large f-numbers).

number ISO NUMBER. The higher the ISO sensitivity, the more 'noise' there is in the photo and the less clear it is.

What are full apertures in photography?

Full apertures are f/1.8, f/2.8, f/4/0, f/5.6, f/8.0, f/11, f/16, f/22, f/32, f/64. They are so named because changing the aperture from f/11 to f/8.0 doubles the amount of light.

Suggested reading:

The verb stop, cease, cease, cease, cease, cease means to stop or interrupt an activity. Stop is applied to an activity or progress or something that is working or progressing and can imply suddenness or certainty.

Pole – a slang term for the death penalty, specifically hanging or beheading.

What is a stop in film photography?

An aperture is doubling or halving the amount of light entering a photo. The term 'aperture' is widely used in photography and plays an important role in the pressing and pressing of film, especially when you are filling out a film development form. A 400 ISO film set at 800 in your camera is underexposed by 1 stop (+1) because it has been doubled.

What is 10 foot photography? If you are just starting to experiment with long exposures, the 10ft filter (ND1000) is the ideal neutral density filter to start with. A 10-stop ND filter allows only 1/1000th of the ambient light to enter the sensor and can be used at sunrise, sunset and the daylight hours in between.

What is an aperture? An aperture is doubling or halving the amount of light that lets through when you take a photograph. For example, if a photographer says they increase the exposure by 1 stop, it simply means that they are catching twice as much light as the previous shot.

diagnostic techniques

If you notice the characteristic swelling, consult a urologist - the earlier the diagnosis is made, the fewer complications await the patient in the future. Do not try to treat on your own and do not put off seeing a doctor!

The specialist will find the appropriate diagnostic methods:

• biochemical and general blood tests;
• General clinical examination of urine, bacteriological tests, daily diuresis;
• Ultrasound examination, computed tomography, magnetic resonance imaging with contrast agent;
• Doppler sonography of the renal vessels.

The urologist can prescribe inpatient or outpatient pharmacological treatment. If surgical intervention is indicated, the doctor will suggest minimally invasive techniques with a short rehabilitation period.

The RM Urology Clinic. The First Moscow State Medical University Fronstein offers high-quality diagnostics for renal edema and state-of-the-art urological treatment. Patients are treated by doctors of the highest category, Doctors of Medical Sciences.

Gagik Nersesovich Hakobyan - Dr. med., Doctor of Medical Sciences, Professor of Urology Department of the First Moscow State Medical University Sechenov.

Treatment of urological diseases

• urolithiasis
  • urolithiasis
  • Kidney stones
  • ureteral stones
  • bladder stones
  • stones in the urinary tract
  • renal cysts
  • angiomyolipoma
  • kidney cancer
  • hydronephrosis
  • Pelvic and ureter tumors
  • stenosis of the ureter
  • inflammation of the kidneys. pyelonephritis of the kidney.
  • tumors of the bladder
  • urinary incontinence
  • ureterocele
  • prostate adenoma
  • prostate cancer
  • urethral stricture
  • testicular cancer
  • Adnexal cyst of the testicle
  • phimosis

  

• X-ray of the foot.
• stop.
• Walking in medium heels.
• photos of the foot.
• Walking school with prosthesis.
• If your soles and heels hurt.
• foot pattern.
• The socks on the big toe are torn.