Moment maps from the RT simulations. Top panels: Moment 1 maps from Monte Carlo radiative transfer simulations i = 0° (left) and i = 30° (right). The grey circle in the bottom left corner represents the corresponding beam size. Middle panels: Moment 9 maps, again obtained from the Monte Carlo radiative transfer of the simulation dump, i = 0° (left) and i = 30° (right). Bottom panels: Brightness-velocity maps, i = 0° (left) and i = 30° (right), for selected pixels for highlighting the large span of different velocity contributions in individual pixels. The maps are obtained after convolving spatially the image with a Gaussian beam of Δs = 0.05 arcsec (marked as a grey circle in the bottom left corner of each image) and Δυ = 0.05 km s⁻¹. We note that the convention about velocities in observations is that blue-shift of lines is associated with negative velocities, while red-shift is associated with positive velocities – for example, this implies that υ_z in this plot is opposite in sign with respect to that in Fig. 7. The case i = 0° shows well how M1 maps tend to underestimate the vertical velocity contribution compared to M9 maps.