Fill Flash as a Solution to Back Light Situation

In this tutorial Michael explains why you need to use a flash (even built in your camera) when shooting in the day light.

When your subject or model is positioned against the light source, for example the sun is behind your subject, you need to compensate the back light. Otherwise your model will be underexposed, i.e. dark, compare to the sky. It happens because the camera metering system tries to expose the sky which is a lot brighter that your subject.

If you are a beginner, set your camera to the "P" mode and have your flash open. Try shooting and you will see that your subject is exposed more relative to the sky. You may have to play with a flash compensation feature on your camera that decreases or increases your flash's output power by 1 to 2 stops. Usually you can adjust the flash power from -2 to +2. If your subject is still darker than you want, try dialing plus 1 or 2 and see how it affects its brightness.

In order to make use of your flash in back light situations, remember that your model needs to be close to your camera (flash). Otherwise the flash power will be insufficient to properly lighten the subject.