In the process of atmospheric radiative transmission in the visible light band, the measured value of sun angle changed along with the remote sensor’s position, and the images received different energy. The basic concepts of solar elevation angle are illustrated and radiative transfer mode code Motran5 is used to quantitatively analyze the difference of energy with various solar elevation angle. By summarizing the method of solar elevation angle correction of other scholars, a model of radiance between different solar elevation angle and 0
sun elevation angle is built by numerical simulation method, a correction method is put forward by means of the model. A comparison between correction and 0
radiance is carried out, relative error of less than 1% shows that the correction is desirable.