The original Tek CCD of the 1m reflector of Yunnan Observatory was damaged in the late 2008, and two new Andor CCD cameras were imported. The second one was once lent by the 2.4m reflector of the Observatory, and then is used at the 60cm reflector. The performance of both CCD cameras have been determined, including the gain, readout noise, linearity and the shutter function, as well as the influence of the scattered light. The results are; the linearity is better than (0.1?0.3) % , but the motion of the shutter is not stable, the shutter function of the #1 CCD determined at different nights are different, and the motion of the shutter of the #2 can not repeat even within one night. The exposure must be longer than 2s in order to let the influence of the shutter less than 1 % ; the influence of the scattered light is obvious, and the systematic difference between the twilight flat field and the night exposure is larger than 2%. Comparing to the previous CCD observations, it is obvious that the above problems come from the new CCD camera itself.%云南天文台1m镜原有的Tek CCD,于2008下半年损坏,换用了新的Andor CCD照相机.共进口了相同的两架.其中第二架在该台60cm望远镜上使用.测试了它们的某些性能.包括这两架CCD照相机的增益(gain),读出噪音(readout noise),线性和快门函数,以及散射光的影响.结果表明:线性极好,非线性小于(0.1～0.3)%;但快门运动不稳定.#1CCD的快门函数在不同夜晚的测定并不相同,#CCD的快门运动在同一夜晚都不重复,无法使用快门函数对短露光做改正,要使快门函数的影响小于1%,需长于2s的露光;散射光的影响明显,晨昏蒙影与夜天平场的系统差可≥2%,对比以前的CCD观测,问题显然来源于新CCD照相机本身.
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