Opacity maps of the CS(2−1) and SO(3₂−2₁) transitions estimated from the intensity ratio of the ³²S and ³⁴ S transitions when the flux of both isotopologues is higher than four times the σ rms noise level and assuming the ³⁴S transitions are optically thin (see text for more details). Black crosses represent the position of the 4A1 and 4A2 sources of the IRAS4A binary system. Green crosses represent the position of the SiO(5–4) emission peaks along the outflows.