The Image Processing in The Digital Zenith Camera
数字天顶摄影仪的图像处理

The efficiency of measurement of vertical deflections was low-level due to the fact that the determination of astronomical coordinates still was difficult. In order to improve it, the digital zenith camera composed of a large-area CCD came into use. The basic principle of measurement mentioned: Firstly practice photography to zenith, searching and subdividing the objects in the sidereal image, computing the astronomical coordinate of the measure position, then combining with the geodetic coordinates measured GPS-equipment (Global Position System), lastly calculate the vertical deflections. With the system itself information, a new arithmetic advanced about rapidly searching for sidereal. This method is verified using process simulation.