Exposure is the amount of light coming into the camera when shooting a photograph. The amount of light is determined by the aperture and shutter speed. By combining them with ISO sensitivity, the brightness of a photograph is determined.
In the auto shooting modes and P/A/S-modes, the automatic exposure (AE) function is activated, so that the camera will judge the optimal exposure and set the aperture, shutter speed, and ISO sensitivity accordingly. By using this AE function, you can shoot photographs with appropriate brightness automatically judged by the camera.
However, depending on situations, the brightness judged to be appropriate by the camera may be different from what you expect. In the photograph shot with the AE function below, the exposure is based on the brightness intermediate between the bright cloud and the dark building. However, if you want to emphasize the towering cloud, the darker image is better. On the other hand, if you want the building to be rendered more clearly, the brighter is better.
Exposure compensation +0.7 Exposure compensation 0 Exposure compensation -0.7
In such cases, using exposure compensation is recommended.
Exposure compensation is an adjustment of the exposure judged to be appropriate by the camera to make it closer to the brightness you want. As in the above example, the appropriate brightness of a photograph varies depending on scenes or your personal preference. If you want to make it brighter, adjust it to the + side, and if you want to make it darker, adjust it to the - side.
With a digital camera, you can check the result of shooting on the spot. Make exposure compensations repeatedly to obtain your desired brightness.