1.When to use Exposure Compensation
Your camera’s metering system is vital when taking pictures. It works out how much light needs to enter the camera for a correct exposure. The problem with metering is that it takes an average reading, which assumes a midtone, halfway between white and black.
When shooting portraits, light skin tones can easily trick the camera into underexposing the shot. You’ll notice this most with full-face photos, or when there’s a lot of white in the scene. Brides at weddings are a good example.
2. Aperture Advice
When shooting portraits, it’s best to use a wide aperture of around f/2.8 to f/5.6 to capture a shallow depth of field, so the background behind the subject is nicely blurred and they stand out better. Shoot in aperture priority mode to control the depth of field, as your DSLR will then set the shutter speed for a correct exposure. Specialist portrait lenses tend to have a wider maximum aperture, from f/1.4 to f/2.8, to blur backgrounds even further.
3. Shutter Speed Setting
When setting your shutter speed, factor in your lens focal length, otherwise camera shake and blurry images will become an issue.
Make sure your shutter speed is faster than your effective focal length. For example, with a 200mm lens, use a shutter speed of 1/250 second or faster. This also means you can get away with slower shutter speeds when using a wide-angle lens, such as 1/20 second with an 18mm focal length.