Performance of the CCD Camera on the 65 cm Reflective Telescope at Nanjing University

We have determined the capability of the Charge-Coupled Device (CCD) system by the dome flat field method on the backend of the 65 cm reflective telescope at the Zuodijiang Observatory of Nanjing University, and have obtained its shutter function. The response linearity of CCD camera has also been tested by the flat field exposure series. The results show that nonlinearity of the readout value is less than 1% from 0 to 61 900 ADU, and the gain of CCD camera is about 1.02e^-/ADU, and the readout noise is about 13e^-. However, overflow has occurred when the readout value is above 38 000 ADU for point-source observation. Therefore, proper exposure time is needed to avoid star image overflow when using this camera for point source observation. In the future observation, this shutter function could be used to calibrate the image in order to improve the photometric precision.