AAVSO visual lightcurve of R Scl (Henden 2009). Colored zones indicate the observing period of Polarimetric measurements (orange) (Yudin & Evans 2002), ISO/SWS measurements (blue) (Sloan et al. 2003), VINCI measurements (violet), MIDI UT measurement (black), and MIDI AT measurements (green). The point surrounded by the open rectangle represents the chosen phase-zero point (φ₀ = 0).