In this paper we analyse the methodology to derive the bar pattern speed from dynamical simulations .
The results are robust to the changes in the vertical-scale height and in the mass-to-light ( M / L ) ratios .
There is a small range of parameters for which the kinematics can be fitted .
We have also taken into account the use of different type of dynamical modelling and the effect of using 2-D vs 1-D models in deriving the pattern speeds .
We conclude that the derivation of the bar streaming motions and strength and position of shocks is not greatly affected by the fluid dynamical model used .
We show new results on the derivation of the pattern speed for NGC 1530 .
The best fit pattern speed is around 10 km s ^ { -1 } kpc ^ { -1 } , which corresponds to a R _ { cor } / R _ { bar } = 1.4 , implying a slower bar than previously derived from more indirect assumptions .
With this pattern speed , the global and most local kinematic features are beautifully reproduced .
However , the simulations fail to reproduce the velocity gradients close to some bright HII regions in the bar .
We have shown from the study of the H { \alpha } equivalent widths that the HII regions that are located further away from the bar dust-lane in its leading side , downstream from the main bar dust-lane , are older than the rest by 1.5–2.5 Myr .
In addition , a clear spatial correlation was found between the location of HII regions , dust spurs on the trailing side of the bar dust-lane , and the loci of maximum velocity gradients parallel to the bar major axis .