Fiducial images produced by the DIFMAP pipeline reconstructed through the implementation of an initial phase-only self-calibration process using a point source model. The reconstructed images exhibit ring-like structures, which are comparable to the results obtained from the pipeline that utilized closure phases to select the optimal geometric model for the initial phase-only self-calibration, as demonstrated in Fig. 7. The circle represents a Gaussian blurring kernel with a FWHM of 20 μas.