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. These, combined with ISO sensitivity, determine the brightness of a photograph.
In the auto shooting modes and P/A/S-modes, the automatic exposure (AE) function is activated. As a result, the camera will determine 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 determined by the camera.
However, depending on the situation, the brightness that the camera determines to be appropriate may differ from what you expect. In the photograph shot with the AE function below, the exposure is based on the intermediate brightness 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 image 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 to the exposure that the camera judges to be appropriate, to make it closer to the brightness you want. As in the above example, the appropriate brightness of a photograph varies depending on the scene or your personal preferences. 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 results of a shot on the spot. Make exposure compensations repeatedly to obtain your desired brightness.