Overview of the nine selected SDF/SSUB events. Top left panel: context Ca II 8542 Å far wing image (−942 mÅ) with the location of the events denoted with small squares, delineating the exact areas that are analysed using inversions. The nine sub-images at the top-right show the SDF–SSUB pairs at their clearest visibility and are selected from Figs. 2–4. These correspond to the fields of view shown in the top left panel with a rotation applied such that the SDF–SSUB pairs are aligned along the y-axis. In all cases the dark SDFs are seen just above the bright SSUBs. The central wavelength of each passband is written in units of Doppler shift from the core. Bottom panels: two SDF–SSUB pairs in context. An image of the line core, scaled such that 30% of the pixels are saturated, is shown at the bottom left. The box highlights SDF–SSUB pair A. Bottom right panel: image taken at +145 mÅ from the line core, with the same 30% saturation, where SDF–SSUB pair H is highlighted with a box. This latter selection perfectly matches the respective image in the top right panel as no rotation was applied.