a) Contrast of the BPs in the G-band as observed in our fields, C. The different smooth fits to the observed CLV. b) Fraction of total solar disk covered by BPs from the solar limb to a particular μ – F in Eq. (4). The three different types of line correspond to the three curves in Fig. 2. c) Fraction of TSI contributed by the quiet Sun BPs – H in Eq. (5). The three different types of thin lines correspond to the three curves in Fig. 2, with the contrast given by the triple-dot dashed line in a). The thick solid line is equivalent to the thin solid line except that the contrast is taken as the dotted line in a).