Amplitude of the diagonal (black) and off-diagonal (gray) terms of the estimated Jones matrices for a remote station using the LOFAR observation synthesized 6′′ image as the sky model (self-calibration). If the initial  DI calibration and correction by  PREFACTOR on the lower resolution TGSS sky model were good enough, the calibration solutions found here would be the unity matrix at all times and frequencies. Therefore, in DDF-PIPELINE-V2, we carry out a few full-Jones DI-only self-calibration steps. This approach seems very efficient in increasing the dynamic range around the brightest radio sources.