NIR and 7 mm light curves on May 17 6:04–12:19 h UT 2012. a)K_s-band (2.2 μm) light curve of Sgr A* observed in polarimetry mode on 17 May 2012. The light curve shown is produced by combining pairs of orthogonal polarization channels: 0° and 90° (for further details see Shahzamanian et al. 2015). b) 7 mm DFT of NRAO 530 and Sgr A* on May 17. Sgr A* was averaged over 15 min. NRAO 530 was averaged over 2 min. c) Detrended 7 mm DFT of Sgr A* on May 17. d) 7 mm light curve derived from the two-hour maps observed on May 17 (see Fig. 4). Fluxes were obtained from delta-component maps (green) and model fitting (blue). Errors represent the formal errors of 1.7% derived from NRAO 530. Not shown are the systematic errors of ~18%, which should be corrected for by calibration.