High-Precision Photometry Based on an Effective Point Spread Function Method

The paper describes the details of a procedure to obtain instrumental stellar magnitudes from CCD images using an ePSF(effective Point Spread Function) fitting method.We conduct an experiment with CCD images.The average internal error of the method is 0.015 mag, while the best errors are 0.001 5 mag for a bright star and 0.043 mag for a faint star.The precision of the ePSF fitting method is 3 times better than the Gaussian fitting method.The rms error of the ePSF fitting method is 0.005 mag.The results show that the ePSF fitting method is stable.