When you take a photograph either inside or out, your camera will determine whether it needs to use the flash or not. And most of the time it does a good job… but not all. When you are faced with shadows its best to turn your flash on. This will lighten shadows and make your photo just that much better.
These images are great examples. Because there is a lot of light coming into the camera, the camera senses “there’s enough light I won’t use the flash”. As you can see by manually turning on the flash it brightens the darker areas (shadows).
Now if you’re at an All Blacks game or a Lorde Concert and you are a long way back then your flash is not going to do anything apart from illuminate the back of the head in front of you. So in this instant you will turn the flash off. The camera will want to go but the light will only reach max 4 or 5 meters. So the opposite rules apply. The camera want to flash but turn it off.