Within a prioritized mode selection dialog, either a measurement accuracy prioritized mode or a measurement speed prioritized mode is selected. If the measurement accuracy prioritized mode is selected, then processing for entering a tolerable amount of movement is executed. Then, a relative movement speed of a CCD camera to a measurement stage is calculated from the entered amount of movement. Finally, image information is captured at a lower speed than the calculated relative movement speed to execute image measurement. If the measurement speed prioritized mode is selected, then processing for entering a relative movement speed is executed, and image information is captured at the entered relative movement speed to execute image measurement.