Cameras with this feature will automatically bring more detail to darker areas of an image when bright lights (usually shining from behind) obscure it.
Button for use in backlight situations which increases the amount of exposure given to the picture - to help avoid silhouetted subjects when shooting against a window, for instance.
Back Lighting Compensation. Is a built-in feature of every camera found on AutomatedSurveillance.com. BLC indicates the image sensor's ability to automatically adjust in conditions where lighting is from behind the camera to deliver the sharpest and highest quality video image possible.