Continuum images of the combined ALMA observations of PDS 70 before (left panel) and after (right panel) self-calibration. The middle panel shows an image obtained after self-calibrating 2015.1.00888.S data and before self-calibrating 2017.A.00006.S data. The color scale has been stretched to highlight improvement on the image noise. White and green contours are draws at 3×  and 6× the rms noise levels, which are equal to 0.022 (left panel), 0.020 (middle panel), 0.018 mJy beam⁻¹ (right panel), respectively.