Exposure:
The action of exposing the sensor or film in a camera to light.
A correct exposure has detail in the highlights and shadows. Correct exposure means an image with maximum detail, that gives us the most options in editing. We use the exposure meter and histograms to help us achieve the correct exposure.
The exposure meter can be found in your viewfinder or on the rear screen of your camera. It helps us to read the amount of available light. Exposure meters vary from camera to camera, but generally look like the one in the image below.
Too much light leads to overexposure:
images that are too bright and have no detail in the light or highlight areas.
Too little lights leads to underexposure:
images that are too dark and have no detail in the dark or shadow areas.
The amount of light entering the camera is controlled by the aperture, shutter speed and ISO (Sensitivity) The Correct exposure will have detail in the highlight and shadows (the brightest and darkest areas) .
