针对空间相机在轨传递函数因包含大气传递函数而难以客观反映空间相机成像性能的问题，依据靶标调制度、相机入瞳前的物方调制度、像方调制度这三种调制度之间的关系，提出了一种可准确测试大气传递函数和不含大气在轨传递函数的方法。利用该方法对空间相机进行测试，结果表明：实时的大气传递函数为0.762，含大气的沿轨传递函数为0.177，不含大气的沿轨传递函数为0.232。实验室测试的传递函数值与不含大气的沿轨传递函数值的相对误差为4.7%。

On-orbit modulation transfer function (MTF) of the space camera usually contains the MTF with atmospheric effect, and therefore it does not objectively reflect the imaging performance of the space camera. Based on the relationship among the modulation depth of the object target, the object target before the entrance pupil of space camera and the image, a novel technique is proposed to exactly test the atmospheric MTF and the on-orbit MTF without atmospheric effect. The test results of a space camera with the above measuring technique indicate that the real time atmospheric MTF is 0.762, the on-orbit MTF with atmosphere effect is 0.177, and the on-orbit MTF without atmospheric effect is 0.232. The relative error between the MTF value measured in the laboratory and the on-orbit MTF without atmospheric effect is 4.7%.