a) Model three-colour J, H and K_s band image for the envelope with disk model (RGB: K, H, and J bands respectively). b) Observed 2MASS three-colour image of AFGL 2591. c) Model J, H, and K_s band image for the envelope without disk model. The model images have been normalised to the total integrated fluxes given in Table 3, in order that the morphology of the emission can be easily compared. Stretch: red: K_s band, 130−300 MJy sr^-1; green: H band, 95−150 MJy sr^-1, blue: J band, 30−60 MJy sr^-1.