UNDERSTANDING EXPOSURE

Exposure is the correct combination of shutter speed, aperture, and ISO speed to get the photograph that you want. Exposure can be determined solely by the camera, by you (as the photographer) and the camera together, or solely by you. Whenever the camera helps you choose exposure settings, the camera’s built-in light meter takes a reading of the reflected light in the scene and then selects the appropriate camera settings.

When taking photos, remember that there is no such thing as a perfect exposure only one that is how you want it to be. Overexposed photographs are overly light, and detail is lost in the highlights. Underexposed photos are overly dark, and detail is lost in the shadows.
Because digital camera exposure metering systems measure light as if it were reflected from a neutral-gray surface, they may misread the light when a scene is very dark or very light. Classic examples include a black cat sitting in front of a large pile of black coal or a white cat sitting on snow.

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