Intensities for the single-scattering component for FU Ori at λ = 12 μm, for the cases where the extended emission is due to a disk (top) and an envelope (bottom), and for different dust models. The central illuminating source is assumed to be a flat compact disk. The white dotted contours in the upper panels are for the disk surface aspect ratio z_disk/r = 0.5; the white dotted contours in the lower panels are for the H band optical thickness in the radial direction τ_r = 0.35 and 0.7; and the black solid contours in the lower panels are for the H band optical thickness along line of sight τ_l = 0.35 and 0.7. The regions with τ_r>0.7 and τ_l>0.7 are hatched in the bottom-right panel. In the top-left panel, the left (east) side of the east arm is masked as the calculations are not self-consistent (see the text).