The application discloses a relative photometry improvement method for an oversaturated detection image, belongs to the technical field of astronomical image photometry, and aims at solving the problem that the nonlinear truncation of the observed
light flux is caused by the oversaturation of the gray value of a star in an existing astronomical image, and the
systematic deviation exists in a classical relative photometry model in a star apparent magnitude
estimation method. The method comprises the following steps: based on a
point spread function model of saturation truncation, a
mathematical relationship between the total
light flux of a star and the observed
light flux of the star in an astronomical oversaturated detection image is established; according to the
mathematical relationship, a relative photometry improvement model is established; based on the observed light fluxes of a plurality of known
stars and corresponding reference apparent magnitudes, an iterative optimization
algorithm is adopted to iteratively optimize the relative photometry improvement model, and the optimal
model parameter in the model is solved; and based on the optimal
model parameter and the observed light flux of a target to be measured, the apparent magnitude
estimation value of the target in the astronomical oversaturated detection image is obtained through the relative photometry improvement model.