Color-magnitude plots from CrAO VR_JI_J photometry. Left: (V − R)_J vs. V. Right: (V − I)_J vs. V. The source gets redder when fainter. The dashed line is the expected reddening line for ISM extinction. The photometric measurements are color-coded by Julian date to distinguish the 2 observing seasons: lighter points correspond to the first epoch, darker points to the second one (see Fig. 2). We note that the deep faintening event of about 1.2 mag in the V-band is accompanied by a strong reddening of the system.