Top: upper panel, data (solid) and best fit (dashed line) for 26 Tau, a binary field star with a high brightness ratio approaching 5 mag. The lower panel shows, displaced by arbitrary offsets and enlarged for clarity, the residuals of the fits by a point-like (below) and by a binary star model (above). The normalized χ² values are 1.44 and 1.09, respectively. The times of the geometrical occultation of two stars are also marked, with their difference corresponding to a separation of 18.5 mas. The inset shows a magnified portion of the data (solid line), and of the fits by a double (upper dashed line) and single (lower dotted line) source. Bottom: brightness profile reconstructed by the model-independent CAL method. The brightness scale is not linear.