HD 100546 stellocentric distance-scaled disk images; an “x” denotes the positions of HD 100546 b and the candidate “HD 100546 c.” (left) Polarized intensity image showing the inner working angle (magenta dashed line) and the star's position (cross). The polarized intensity drops interior to 0.″15–0.″2. The dark blue regions west of the visible disk identify the dark lane (Grady et al. 2001, 2005). (right) Spatially filtered, wavelength-collapsed IFS image showing the thermal IR-bright spiral-like feature (1), a second spiral (2), the position of the proposed spiral identified by Avenhaus et al. (2014) (3), and the western rim of the visible disk (4).