Noise curves of J1850-3147 measured from the residual image at multiple wavelengths as a function of stellar flux obtained before performing HRSDI. Fittings of two noise components are shown as cyan (fitting only with Hα data) and yellow lines (fitting without Hα data). The noise curves are close to the theoretical limit of photon noise at small separations (<0.6′′ ; yellow shaded region). The fitting results are presented in Table 3.