Exposure Compensation is another great tool to break your dependency on the automatic flash for lighting! Exposure is the term used to describe how bright or dark the outcome of your photo is.
Your camera guesses the exposure of your photo by metering the light in various areas of your photograph, but sometimes it guesses incorrectly.
For example, think of a person sitting in front of a dark background. The camera might see all those dark colors and try to make them properly lit (or "exposed"), but at that same exposure the person might look too bright, or overexposed. On the other side of the spectrum, if you are photographing a person in front of a very bright background, like a sunny sky, the camera might see the bright light and properly exposed it, but your subject will end up underexposed, or too dark at that same exposure setting.
Exposure compensation is how you correct for improper exposure. It's scale that uses (+) or (-) values. Moving the exposure to a positive value will brighten your image, and moving it to a negative value will darken your image.
Simply put, metering tells the camera how much light there is in the scene so it can correctly expose the image. There are three settings your camera generally uses to "read" the light in the scene: center weighted, spot and the default, matrix metering.
Center-weighted metering: The camera "weighs" the center of a photo and considers it more heavily when making it's "decision" on how to properly expose the image.
- Center-weighted metering is the best to use for portrait photography, because it will guarantee that your subject is correctly exposed without heavily considering the background. Meaning, it will draw attention to your subject, not the background. You would center-weighted metering when it is important to get the exposure of your subject correct, rather than the background.
Spot metering: Like center weighted metering, the camera uses the center of a photo to measure the light to determine the correct exposure. The difference with spot metering is that it uses a smaller area to make the determination.
- Spot metering is good to use when your subject is significantly darker or lighter than its surroundings.
Matrix metering: The camera looks at how the light is distributed throughout the scene, and reads the light and dark zones to try and balance the exposure in the image. Matrix metering usually does a pretty good job, but occasionally will get it completely wrong and is unpredictable.
- Matrix metering is good for scenes that are evenly lit and times when you need to capture shots quickly