Fiducual images of the 2017 April 11 low-band data obtained from the 2018 DIFMAP pipelines discussed in Sect. 5.1.1, as a backwards compatibility check. The top row of images is obtained using the pipeline that conducts initial phase-only self-calibration by employing a point source model, whereas the bottom row of images is obtained from the pipeline that identifies the optimal geometric model for self-calibration. The circles represent a Gaussian blurring kernel with a FWHM of 20 μas.