Effects of two calibration steps on imaging artifacts and flux absorption. Left-hand panel: shows that a faint and unmodeled extended emission (on the level of ~ 0.7σ here) can be totally absorbed. While regularizing the DD calibration solutions can help in recovering the unmodeled emission (typically after Step 1.16), it can also produce negative imaging artifacts and “holes” around bright sources (central panel). Right-hand panel: shows that solving the residuals on longer time intervals (Step 1.17) corrects for this issue.