False-colour image of the three-component model for the mid-infrared emission of the nucleus of the Circinus galaxy (fit 3). The colours red, green and blue correspond to the model at 13.0 μm, 10.5 μm and 8.0 μm, respectively. The colour scaling is logarithmic in order to show both bright and faint features. Clearly the colour gradient of the extended component due to the increase in the silicate depth towards the south-east is visible. This colour gradient leads to a chromatic photocentre shift towards the north-west. Despite the lower surface brightness, 80% of the emission comes from the extended component. Also plotted is the trace of the water maser disk: the blue and red parts trace the approaching and receding sides of the maser disk respectively. Note that the relative offset of the mid-infrared emission with respect to the maser disk is not known (see text for details).