Monday 19 March 2018

How to Understand Your Camera’s Exposure Compensation Feature

In this article, learn about the Exposure Compensation feature on your camera to get the best exposures.

Whether you’re shooting sports, animals, portraits, toys, snowflakes, rocks, fish, weddings, or pretty much anything else you almost always have one goal in mind. You want your pictures to be properly exposed. Of course, you can fix an image in Photoshop if it’s too light or too dark, and shooting RAW definitely helps with that. But over the years I’ve found that the best solution is to just get your exposure right in camera.

This means finding the right combination of aperture, shutter speed, and ISO to get your image to look the way you want. But there’s another option you have at your disposal as well – your camera’s Exposure Compensation feature. Understanding what this does and how it works can help you get your pictures looking pixel-perfect in camera without having to adjust anything afterward.

How to Understand Your Camera's Exposure Compensation Feature - photo of a goose

What is Exposure Compensation?

Buried deep in the computational brain of your camera is something called a light meter whose job it is to measure the amount of light entering the lens. This lets your camera adjust some of the exposure settings automatically or gives you enough information for you to make adjustments yourself.

The problem with metering and the camera choosing the exposure

Depending on how you have your metering mode set up it might look at all the light coming in through lens, just the part in the center, or sometimes only the light where you have your focus point set.

As your camera takes measurements of the incoming light and adjusts exposure settings it tries as hard as it can to get a picture that is properly exposed. It might make the aperture larger or smaller, adjust the shutter speed, change the ISO or use a combination of all three of those techniques just to make sure the photo comes out right.

The trouble is, your camera doesn’t always have a good sense of how you want your picture to look.

How to Understand Your Camera's Exposure Compensation Feature - photo of a young man

My camera tried to make this image much darker because of all the light behind this young man, so I used exposure compensation to make the background slightly overexposed which meant my subject was properly exposed.

Enter the solution

Sometimes you might want your picture to be slightly over (lighter) or underexposed (darker), and this is where the exposure compensation feature really starts to shine. If you notice that your images aren’t coming out quite as light or as dark as you want them, you can either change the aperture, shutter, or ISO yourself.

Or just tell your camera “Hey, brighten things up a bit will you?” and with a quick twist of the Exposure Compensation dial, voilà, your problems are solved.

Most people find Exposure Compensation to be particularly useful when shooting in a semi-manual mode such as Aperture or Shutter Priority, but you can use it in other modes as well like program auto or even full manual.

In order to dispel some of the mystery surrounding the exposure compensation feature, let’s take a look at what your camera is actually doing to the settings when you use it in any of those modes.

General Notes for Using Exposure Compensation

NOTE: Please make note that when you dial in any Exposure Compensation it does not get reset to zero automatically for your next shot. You need to change it yourself manually once you’re done using it.

PROBLEM: One of the biggest problems beginners have is not realizing their Exposure Compensation is active. If you have erratic exposures, or all your images are either too dark or too light – check to see if the Exposure Compensation dial has been moved and correct it to zero if necessary. 

How to Understand Your Camera's Exposure Compensation Feature

“How does exposure compensation work? Please, tell us more!”

Aperture Priority Mode

Most photographers I know shoot primarily in Aperture Priority mode because of the way aperture affects depth of field and other critical elements of the composition. I use this mode almost exclusively, usually combined with auto-ISO to make sure my shutter speed never gets too slow, and it works like a charm.

I like adjusting my aperture and letting my camera take care of everything else because nine times out of ten it’s just easier for the way I prefer to shoot. If I notice my pictures are too bright or too dark I just adjust the Exposure Compensation to take care of it.

When shooting in Aperture Priority, adjusting the Exposure Compensation doesn’t ever change your aperture–doing so would defeat the whole purpose of using this mode! Instead, it changes the shutter speed by either speeding it up or slowing it down in order to make your picture brighter or darker.

How it works

In the image below, shot in Aperture Priority, you can see that the subject is way too dark while the background is properly exposed. This is partially a result of my camera’s metering mode but also because the scene itself contains a high degree of dynamic range and is therefore tricky to get just right.

How to Understand Your Camera's Exposure Compensation Feature

Aperture Priority, 200mm, 1/750th, f/4.0, ISO 100, no Exposure Compensation.

To fix the problem I could have changed my camera’s metering mode but instead, I chose to dial in an exposure compensation value of +2EV. The result left the background totally blown out while giving me a properly-exposed subject.

How to Understand Your Camera's Exposure Compensation Feature

Aperture Priority, 200mm, 1/180th, f/4.0, ISO 100, +2EV Exposure Compensation.

The key takeaway is that while the focal length, aperture, and ISO values did not change the shutter speed most certainly did. My camera dropped it all the way down to 1/180 second which let in much more light and therefore resulted in a two-stop overexposure from the original.

When using exposure compensation in Aperture Priority your camera will adjust the shutter speed to be faster or slower, which can make a big difference if you are shooting a moving subject. You might want a fast shutter speed but if you’re dialing in a few stops of exposure compensation you might end up with one that is too slow to capture the image you are going for.

It’s not a problem per se, but it is something to note and it could dramatically affect your images if you aren’t aware of what is happening. If you need a faster shutter speed you can increase the ISO a bit also.

Shutter Priority

In a similar vein, using Exposure Compensation when shooting in Shutter Priority will not change your shutter speed but will instead alter the aperture in order to make your image lighter or darker.

When I shot the image below of a duck on a frozen pond I wanted a fast shutter speed in case my avian friend started moving quickly. So I used Shutter Priority with a speed of 1/250th of a second.

How to Understand Your Camera's Exposure Compensation Feature

Shutter Priority, 200mm, 1/250th, f/8.0, ISO 100, no Exposure Compensation.

You can probably tell that something isn’t right with the photo. The duck is too dark! I had to lighten the composition quickly before it flew away, so I dialed in a value of +1.5EV on my Exposure Compensation.

How to Understand Your Camera's Exposure Compensation Feature

Shutter Priority, 200mm, 1/250, f/4.8, ISO 100, +1.5EV Exposure Compensation.

This image is a bit different from the static wood carving in the aperture priority example because you can clearly see the effect that exposure compensation has had on the composition. My camera kept the shutter speed unchanged but used a much wider aperture which gave me an image with far less depth of field. Notice how both the foreground and the background are much blurrier – a direct result of shooting with a wider aperture.

What about ISO

You might have noticed that a third exposure parameter has thus far remained unchanged, that of the ISO. While it’s standard for most cameras to alter the aperture and shutter speed when using Exposure Compensation, ISO is usually the last parameter to get changed unless you are using Auto ISO.

In that case, your camera will most definitely change the ISO if it needs to, especially if shooting in Aperture Priority and your minimum shutter speed (as set up in your settings) has been reached.

How to Understand Your Camera's Exposure Compensation Feature

I had to use a fast shutter speed on this image and didn’t care too much about aperture, so I shot in Shutter Priority and used Exposure Compensation to get the image to look how I wanted. I did not use Auto-ISO because I wanted a nice clean picture, so my camera adjusted only the aperture when I dialed in the Exposure Compensation.

Manual Mode

NOTE: This only applies to Nikon shooters! If you use Canon, Fuji or another brand Exposure Compensation does not have any effect in Manual Mode.

Exposure Compensation in Manual Mode works a bit differently because nothing changes at all when you dial in a value. Instead, it’s your camera’s light meter itself that changes so you can adjust the aperture, shutter, and ISO values manually in order to get your picture to look how you want.

It’s an interesting twist on things that might seem a little strange at first if you are used to having things automatically change when you adjust exposure compensation, but once you start using this method you may not ever want to go back.

It essentially gives you the best of all worlds by letting you adjust exposure settings to get the value you are looking for, you can then choose precisely the parameters you want to change.

How to Understand Your Camera's Exposure Compensation Feature

In Manual Mode, adjusting Exposure Compensation only changes how your light meter displays exposure. Notice how the vertical line indicating the point of proper exposure has shifted to the left when dialing in an Exposure Compensation value of +2EV.

The magic of mirrorless

I know the subject of mirrorless cameras versus DSLRs can be a bit of a thorny one for some photographers, but I would be remiss if I didn’t at least mention it here in an article about exposure compensation.

While the same logic applies regarding Aperture and Shutter Priority modes, the big difference is how you can actually see your exposure settings change in real-time as you look at your camera.

How to Understand Your Camera's Exposure Compensation Feature

This rear screen of this mirrorless Fuji X100F shows me that the photo will be properly exposed.

This is one of the main strengths of shooting mirrorless, though it should be noted that DSLRs can also this in Live View–albeit usually with some tradeoffs such as slower autofocus that usually happens when utilizing Live View.

How to Understand Your Camera's Exposure Compensation Feature

I can see the result of a -1EV Exposure Compensation on the digital readouts (i.e. light meter, histogram, etc.) but most notably the image itself has decreased in brightness as well. This helps me get a very good idea of what effect this Exposure Compensation will have on the final image.

Conclusion

I used to be somewhat scared of using Exposure Compensation because I didn’t really understand what was happening when I changed its value. With a much better idea of what my camera is changing, and why, I am now much more comfortable using it on a daily basis to get my shots to look how I want.

In fact, I often won’t even change my metering modes anymore and instead just rely on Exposure Compensation because I know what it’s doing to my photos and I’m not scared of using it. If you have never used it much either, you might want to go ahead and give a try. You just might like it.

The post How to Understand Your Camera’s Exposure Compensation Feature by Simon Ringsmuth appeared first on Digital Photography School.



from Digital Photography School https://digital-photography-school.com/understand-your-cameras-exposure-compensation-feature/

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