Exposition. Exposure compensation.

Exposure is the amount of light needed to create a photograph. Nothing complicated.

Exposition. Exposure compensation

Exposition. Exposure compensation

The exposure is dosed by fixed assets:

  1. Shutter speed
  2. Aperture
  3. ISO sensitivity value
  4. Flash (or other lighting fixtures)

Basically, in digital photography it is customary to say that exposure depends only on excerpts, aperture, and ISO, but in fact everyone who says so omits the flash.

Exposure is measured in units of exposure EV (Exposure Value).

Image exposure unchanged + -0

Image exposure unchanged + -0

Important: if you fix the ISO value and flash power (as, for example, on old film cameras), it will remain possible to change only the shutter speed of the camera and the aperture of the lens. In this case, shutter speed and aperture are called expocouple. They are a couple, because when one changes, the other adapts to the second. This adjustment is just carried out by the camera.

The most important: changing one of the parameters of the main four, you need to change one of the other three to save the current exposure. So, changing the shutter speed, you will need to either change the aperture value or the ISO value to save the current exposure value.

The exposure is shifted 1.33 steps to the left, since the picture has a lot of dark areas

The exposure is shifted 1.33 steps to the left, since the picture has a lot of dark areas

The exposure meter is responsible for correct exposure in the camera. The light meter is a special sensor in the camera that measures the amount of light “absorbed” by the lens and calculates the “correct” parameters excerpts, aperture, and ISO, and sometimes flash output to create the “correct” exposure.

Correct exposure usually means filling the image with light and dark in a balanced way, usually the meter tries to make the “correct” histogram. In general, how an exposure meter does this is very difficult to explain on the fingers.

The exposure is shifted 1.33 steps to the left, although, according to the idea, it was necessary to shift to the right.

The exposure is shifted 1.33 steps to the left, although, according to the idea, it was necessary to shift to the right. This is the specifics of the camera itself.

Auto Exposure Metering

In automatic modes, in virtually all modes except P, A, S, M, the camera completely determines the parameters excerpts, aperture and ISO. If the flash is on, the flash output is also calculated. Depending on the shooting mode, the priorities of one or another parameter in the exposure are calculated.

no exposure compensation

no exposure compensation

Exposure compensation

Usually the camera (camera) has the ability to shift the overall exposure of the picture to the left or right along the histogram (either add the amount of light, or reduce the amount of light). A special button is responsible for this, which is very easy to find, it has the designation “+ -“. For example, on Nikon cameras, the “+ -” correction can only be used in creative modes P, A, S, M, in all other modes, the correction will not be available.

Exposure compensation

Exposure compensation. You can clearly see what has changed. -1, 0, +1

Exposure Compensation with the Flash Off and the Auto ISO Off:

1. In A (Aperture Priority) mode - when using “+ -”, the camera will vary the shutter speed to compensate for the exposure

2. In S mode (priority excerpts) - when "+ -" is used, the camera will change the aperture to compensate for the exposure

3. In M mode (manual mode) - the camera will not respond to “+ -” correction if the AUTO ISO function is off. If AUTO ISO is on, the camera will change the ISO value.

4. In P mode (program mode) - the camera can change both shutter speed and aperture

If the flash is on, then the compensation occurs with a change in the flash output and other parameters. Especially when the flash is on (in TTL auto flash output mode), the “+ -” compensation is strongly felt in manual mode M.

The camera’s exposure meter does a good job with some tasks.

The camera’s exposure meter does a good job with some tasks. And the amendment does not need to be used

Flash Compensation

Another complication when dealing with “+ -” is the separate flash level compensation function. This function has the same icon as “+ -“, but also adds a lightning bolt. This function directly affects flash level compensation. Changes in the same way, by a certain amount of EV It is very difficult to calculate flash level and exposure compensation at the same time. For example, if normal exposure compensation is turned on “+ -” at + 0.3EV and “Lightning + -” at + 0.7EV, then the overall exposure will have an offset of + 1EV.

Shooting in difficult fog conditions requires exposure compensation

Shooting in difficult fog conditions requires exposure compensation

Even worse, the flash output when using external flashes changes in two places - on the camera and on the flash itself. The camera can have a flash output correction of + 1E.V., And on the very external flash there may be a power correction of -0.7EV in the end, the photo will receive + 0.3EV general exposure corrections from the standard that the camera's automation will offer.

And if you wind all three values ​​of exposure compensation: flashes in the camera menu, external flash and total exposure, the damn leg will break down to calculate the final result.

Strong exposure compensation to the left (in the direction of the shadows) to give the picture the desired effect

Strong exposure compensation to the left (towards the shadows) to give the image the desired silhouette effect.

Why exposure compensation is needed

Correction is needed to create the necessary exposure for the photographer. The camera is always trying to do something in between, which is not at all suitable for creating the desired effect on the photo. Therefore, the photographer makes an amendment and gets either a slightly lighter shot, or a little dark.

Isn't it more convenient to use manual mode instead of exposure compensation?

No, it is not more convenient when active shooting is in progress, it is best to work in the semiautomatic device P, A, S and make corrections, rather than taking pictures at random. As my experience shows, the fully manual mode is only good for unhurried scenes, photo experiments, studio shooting. If you shoot in a semi-automatic P, A, S, then usually the camera makes a more or less normal exposure, which is easy to hold out by shooting in RAW.

Why is exposure compensation necessary in manual mode M?

  1. When the flash is on, modern cameras still measure the exposure and, using the flash power, try to make the “correct picture”, taking into account the correction from the measured norm. The correction only works if the scene is underexposed according to the camera.
  2. With auto ISO turned on, modern cameras also still take exposure metering and try to take the “correct shot” by adjusting the ISO, taking into account the correction from the measured rate.
  3. In the viewfinder, it is convenient to watch exposure deviations with the indicated correction from the norm that the camera shows.
  4. When switching to another mode, for example P, A, S the correction “+ -” starts working, sometimes it is very convenient.
Strong exposure adjustment left

Strong exposure adjustment to the left in order to save the skin texture from overexposure, frequent reception when shooting people

When should exposure compensation be used?

In fact, it is the photographer who decides when and why he needs to perform exposure compensation. There are general recommendations:

  • Increase compensation when shooting white on white
  • Zoom out when shooting black on black (black cat on a black background)
  • The usual exposure compensation when the camera's metering "lies".

But, each modern digital-SLR camera has its own metering, which measures according to its own criteria. You need to get used to your own camera, to know exactly in which scenes the camera will “overexpose” or “under-light”. Here's an actual example: my simple camera Nikon D80 It has a poor property of shifting the exposure to light tones, thereby making the scene overexposed.

Personal experience

I often use exposure compensation. Basically, no more than + -2 ev. All modern CZKs have this function, and it is very convenient and practical. I don’t give advice on setting the exposure, as everyone must decide how to emphasize the atmosphere in the photo with the help of the exposure.

Sometimes with a flash, the camera normally works on exposure

Sometimes with a flash, the camera normally works on exposure

Nothing is clear and complicated

If you don’t know how, it’s better to adjust the exposure, try using bracketing escorts. Even easier, shoot in RAW and adjust the exposure with a RAW converter such as Adobe Camera Raw, Adobe Lightroom, and native camera software. From RAW, you can indulge in an exposure compensation of + -2 EV with virtually no loss of quality

Exposure-corrected flashlight light

Exposure-corrected flashlight light

Conclusion:

Exposure compensation helps you achieve the desired effect in photography and simply correct the automatic exposure metering in the camera. Exposure compensation is a creative element that always needs to be individually adjusted with each shot. If you have questions about exposure compensation, ask in the comments, as the topic is quite complex. I advise you to familiarize yourself with a related topic - metering methods.

Help to the project. Thanks for attention. Arkady Shapoval.

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Comments: 147, on the topic: Exposition. Exposure compensation.

  • BB

    To fix
    'In general, how ExponomerRT does it is very difficult to explain on the fingers'

  • Lion0608

    By the way, isn’t it considered something shameful, whether in the environment of photographers, such parameters as the exposure should be adjusted on the computer?)) The fact is that I noticed that either I suffer from underexposed frames, or does the RAW format have such feature?

    Always the pictures in A mode seem dark and the converter confirms this visually, at almost any aperture and shutter speed. (I have a maximum of 3.5). Although sometimes there are situations when the moment for a picture (non-stop) occurs instantly and with completely different lighting parameters than the photographer expected-measured. What if then the picture is taken with the wrong exposure? Thanks.

    • Denis

      I read somewhere that Nikon does this on purpose, so that there would be no overexposure. maybe bike)

      • Lion0608

        Found my mistake !!! Exposure compensation can be carried out in two modes in the 90th (on the pressed + button - on the top panel of the case (always) or without it in auto modes). Apparently playful hands. I initially had minus 2ev, removed the amendment).
        So, in my case, it's more like stories about armless photographers.
        Thanks for the help

        • Jury

          Menu item b2: Easy exposure compensation. If set to On, exposure compensation can be set by rotating one of the command dials. If set to Off, exposure compensation can only be set by pressing the “+/-” button and rotating the main command dial.

        • yarkiy

          Do not be afraid of exposure compensation, in some cases, it is preferable to “under-light” the frame and then stretch it out in the editor, than to overexpose and throw it away, or get the required exposure and lose sharpness due to a long exposure, and as a result, the frame is also thrown out.
          It is easier to extract information from shadows than from overexposures. "Embossed" colors are actually a lack of information.

          • Lion0608

            Thank you, just the last time there was just enough lighting, and doing the same changes in the Rav Converter was a little depressing. But I’ll take into account the future

    • Jury

      "What to do then if the picture was taken with the wrong exposure?" If you shoot in RAW - adjust the exposure in the editor, if the camera allows - make adjustments to the exposure metering in the camera.

    • Jury

      Yes, the whole point is that no automation, on most cameras, is able to adequately, according to the tasks set for a particular scene, set the correct exposure, that's why cameras with a high dynamic range are so valuable - so that later you can correct the light and shadows manually ... Here, a wonderful person explained everything about the inconsistency of automatic and semi-automatic exposure modes -
      http://photo-element.ru/book/exposition/exposition.html (Arkady, I apologize for the earlier link to someone else's article from someone else's similar site, I hope you don’t “explain” me for that))). Only you can accurately set the exposure, using, for example, an expensive spotmeter with a mode of averaging several metering points (there is a Seconik with averaging over 9 metering points) or using the camera's built-in exposure meter in the spot metering mode, having previously determined the maximum point of light and the point of maximum shadows , followed by the choice of the middle stop. That is, you need to find 2 points of maximum light and maximum shadows, between which you should evenly distribute the entire dynamic range that is maximally accessible by the technical capabilities of the camera, and not the necessary parts of the scene (for example, the failure of a window opening - you do not need to capture that there is in the room behind the opening, or here's another example - a brightly burning lantern in the scene can give out such underexposure that then the shadows cannot be brought out by any correctors) so that they would fall into underexposure or overexposure. Pointing the camera to one point, measuring, pointing the camera to the second point, measuring by counting the number of all switched steps, and unscrewing the wheel towards the first metering by half of all counted steps - this is the most accurate manual exposure metering - three turns of the shutter speed wheel, and you will surpass accuracy of metering any automation and semi-automatic (I mean semi-automatic "A" and "P" modes, or fully automatic "M" mode), the main thing is correct, from the artistic design, to choose the maximum point of Lights and maximum point of shadows, and more importantly, so that the tone and reflectivity of the measured points are approximately equal (well, for example, so that one point on the mirror surface is not measured, and the other is in the hole of some cave - here you will obviously get an incorrect interpolation). But, the only thing, in such a manual multi-metering, you will not be able to work in the genre of “reportage” shooting - this is only for unhurried, unhurried, thoughtful work, but in “reportage” shooting, you still have to rely on three main modes of automatic and semi-automatic filming ... I described in more detail above in the comments. From Uv.

  • BB

    No, your technique is clear to me.
    But an interesting opportunity to shoot a landscape with a large depth of field, shooting several frames at a relatively open aperture, with aiming at different distances, followed by 'stitching' the frames, similar to stacking macro shooting.

  • Ruslan

    Hello! Tell me please!? When you look and see in the viewfinder, the exposure meter shows the number of pictures in plus! This means you need to adjust the pictures on the contrary minus ??? I got a little confused litter!

  • Dmitriy

    Hello, Arkady.
    Could you share your thoughts on exposure compensation when shooting in fog. Many Internet articles recommend + (1-2) ev, but in the literature I have come across recommendations minus (1-2) ev.

  • Sergei

    The Nikon F75 automatically sets the DX-code sensitivity of the film, which cannot be changed manually. When using a cassette with no DX-code, it sets ISO 100. If there is a film in a cassette without a code, with ISO 250, what kind of exposure should be set for correct exposure?

    • Arkady Shapoval

      -1 1 / 3

    • Dmitry

      On the F75, it will only work - 1.5 EV, since the exposure adjustment in this carcass changes only in 0.5 stop increments. You probably won't notice the difference between -1.33 and -1.5.

  • Sergei

    Thank you very much for the help.
    That is, you can use the third-stage GOST standard (GOST 10691-84).

  • anonym

    It is also overlooked to use it by selecting the exposure metering button with the sensor pointing at the desired part in the frame, with the spot and center weighted mode on the area of ​​the frame with no light. In this case, set the correction with a minus, because the light area of ​​the frame has an advantage in metering the exposure meter. and gains an advantage for itself in a shorter exposure, and the rest of the areas will not be supplemented, i.e. dark, and with a large grain. For example, night shooting of an illuminated area framed by multi-storey buildings with dark windows. As a rule, exposure metering in the camera is set in matrix mode, and the illuminated area from night lights and cars gets an exposure for itself, i.e. shorter than the surrounding dark objects, therefore walls with windows and different columns will not receive additional light, and will be poorly visible, it turns out that shiny rails, asphalt, bright points of lamps on poles, and car headlights are striking. the theory of the addition of positive ex-correction, when we want to lighten the area in the frame. Maybe I understood this, as a locomotive driver who received crusts after the end of the course, on the last question to the commission asked: “where the oxen were hidden in the locomotive, he’s going, but the oxen are not visible ”.

  • anonym

    In the Nikon D200, as soon as you turn on the camera and do not press a single button, automatic metering takes place, which constantly changes, depending on the amount of light passing through the lens. These camera actions are visible on the top screen. Because of this, it seems to me that this model consumes a lot of energy, which very quickly affects the battery.
    Question: Is it possible to disable this forced function? On other models, there is no such excess.

    • KalekseyG

      You can reduce the time of her work

    • Arkady Shapoval

      You can set the duration of the metering from 1 second to infinity. It is set in the menu.

  • Yana

    Hello! Please tell me why, every thief frame is underexposed. is it lighter than the first, the third is normal, the fourth is lighter?

    • R'RёS,R ° F "RёR№

      Maybe one point exposure?

    • Artem

      Can bracketing enabled.

  • anonym

    mura. no manual camera control ... in most cases it certainly helps.
    How to remove, (lubricate) the foreground and highlight the background? In manual mode? I can not find….

  • Alexander

    mura. no manual camera control ... in most cases it certainly helps.
    How to remove, (lubricate) the foreground and highlight the background? In manual mode? I can not find….

    • Artem

      There is a button on the camera. Look to the left of the "masterpiece" button.

    • Valery A.

      Look at the depth of field calculator, hyper-focal AF - roughly speaking, from it to infinity, and the foreground is blurred. The mode, of course, is not automatic, but A or M (aperture control).

      • Artem

        Incorrect answer! Dramatically everything from half hyperfocal. The calculator for the phone, of course, can clearly show, but you will need to focus on the accented object. The diaphragm control the influenza zone.

  • Tatyana

    Thanks, very helpful article.

  • Maria

    I’ve been returning to this article all the time, but some points are doubtful.
    A simple example, a bright but cloudy day. In 90% of cases, the sky, which usually becomes part of the background, turns out to be just white (lightly lit). Although the eye visually perceives it all the way a little bluish or slightly grayish.
    I use auto ISO (I call this setting “automatic because the camera adjusts in one way or another to my choice of shutter speed and aperture”).

    In general, in raw you can of course achieve that the sky has distinguishable tones.
    But is the broken sky in such cases a gross mistake and is it worth fighting (with other things being equal) at the time of shooting.

    • Arkady Shapoval

      Rather, these are the limitations of photographic equipment. If the shot looks complete and the broken sky is not a distraction, then this is perfectly acceptable.

      • Maria

        Thank you!

    • Roman

      If the sky is important, shoot across the sky, then drag out everything else with the Darks slider. If it is important what is in the shadows, shoot in the shadows, then tighten the sky with the Whites point. You won't be able to pull everything right away. Especially on a cloudy day - the sky is milky and without details.

      • Maria

        Thank you!

  • Novel

    Yes, the author is right, the topic is really quite complicated. For me, so far. And given the different shooting conditions and what we want to emphasize or, on the contrary, hide in each specific case, it can be quite difficult to understand the direction of exposure compensation. On the second page with comments, one of the readers, just as I thought, that Arkady was mistaken, pointing to the exposure compensation to the left by 1,33. Indeed, logically, in order not to lose the dark areas, they need to be illuminated more, but it turns out on the contrary that in this case, on the contrary, less light should enter the camera…. But if so, does it mean that these dark areas will become even darker? It turns out that no. The author writes that the camera's exposure metering will try to average them. I reread it several times, but still did not understand the logic of these actions ...

  • Igor

    For example, on Nikon cameras, the “+ -” correction can only be used in creative modes P, A, S, M; in all other modes, the correction will not be available. and WHAT OTHER MODES DO YOU HAVE VIEW - CARTOON?

    • Arkady Shapoval

      Amateur cameras have automatic or script modes

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Russian-version of this article https://radojuva.com/en/2012/07/exposure-compensation/