What is exposure?
First of all we need to define what we mean by exposure. Exposure refers to the amount of light that enters the camera and hits the digital sensor. Basically, it is a measure of how dark or bright a photograph is.
If the image is too bright, it is overexposed. Too much light has been allowed to hit the sensor. If it is too dark, it is underexposed. Not enough light has been allowed to hit the sensor. We can control how much light reaches the sensor by changing the aperture, shutter speed and ISO settings.
Exposure is measured in ‘stops’. For example, if you find that your photo has turned out too dark (underexposed), you may increase your exposure by a ‘stop’ or two to make it brighter. Conversely, if the image is overexposed, you may need to decrease the exposure by a stop or two. There is no such thing as the ‘perfect’ exposure, only the right exposure for the photograph you are creating. Some photos such as night shots are supposed to be dark while photos taken in the snow for example are supposed to be bright.
Examples of normal exposed , underexposed and overexposed photographs
Underexposed photograph: There are lots of clipped shadows on the picture.
Overexposed photograph:There are a lot of clipped highlights is this photo.
