1.3 mm continuum emission maps for HD 163296.From left: observed map; emission map for preferred model (Col. 3 in Table 6); residuals for preferred model; emission map for power-law model (Col. 4 in Table 6); residuals for power-law model. Residuals computed by subtracting the model intensity from the observed intensity. Contours spaced at 12 mJy intervals, corresponding to [3,6,9,12,15,18,21,24,27,30,33,36,39,42,45] ×    σ.