The maximum tolerable spot displacement of the Shack-Hartmann wave-front sensor is called dynamic range, and it is
limited by the <i>f</i>-number of the micro-lens. It is well known that there is a trade-off between the sensitivity and the
dynamic range, if the <i>f</i>-number is relatively short, a high dynamic range is achieved, but the corresponding sensitivity is
degraded and vice versa. Extrapolation method could overcome the trade-off; since the extrapolation method is a simple
algorithm that does not change the measurement configuration, there is no requirement for extra hardware, multiple
measurements, or complicated algorithms. In this paper, we not only present the theory but also actually implement
measurement of a highly aerated wave-front.