  Observations have demonstrated the presence of substantial amounts of
interstellar dust in elliptical galaxies, most of which is believed to be
distributed diffusely over the galaxy. Absorption by dust grains has a major
impact on the transfer of stellar radiation, and affects the projection of each
physical (and kinematic) quantity. In a previous paper, we have investigated
the effects of a diffusely distributed dust component on the observed
kinematics of spherical galaxies. In this paper we investigate the effect of
not taking dust into account in dynamical modelling procedures. We use a set of
semi-analytical dusty galaxy models to create synthetic LOSVD data sets, which
we then model as if no dust were present.
  We find some considerable differences between the best-fitting models and the
input models, and we find that these differences are dependent on the orbital
structure of the input galaxy. For radial and isotropic models on the one hand,
we find that the dynamical mass of the models decreases nearly linearly with
optical depth, with an amount of 5 per cent per optical depth unit, whereas
their orbital structure is hardly affected. For tangential models on the other
hand, the dynamical mass decrease is smaller, but their orbital structure is
affected: their distribution functions appears less tangentially anisotropic.
For all models the mass-to-light ratio will be underestimated, by a factor of
around 20 per cent per optical depth unit.
  We discuss these results in the light of the limited effects of dust
extinction on the LOSVDs, as obtained in paper I, and conclude that the
determination of the dynamical mass and the kinematic structure of galaxies...
(for full abstract, see paper)
