Qualitative comparison between a simulation-precision velocity map (left), and against artificially lowered spatial resolution, simulation with a Gaussian kernel convolution. Kernels with angular size (in proportions of the target) 7% (center), and a 3 times larger one 21% (right) are shown. With the distance of HD 142527, the center panel corresponds to the recent high resolution obtained by Keppler et al. (2019). No noise is added. Projected velocities are shown in linear gray-scale, where is shown in light gray and shown in is dark gray. Secondary spiral patterns are lost at low resolution but the primary remains visible. Beam size is shown as a black dot. The velocity map corresponds to the rightmost panel in Fig. 9.