Parallax standard errors for supergiants in the Hipparcos Catalogue, after van Leeuwen’s reprocessing. The dashed line represents 1.5 times the standard parallax error for stars with precise parallaxes (<10%; solid line) in van Leeuwen’s reprocessing (see Fig. 2.19 of van Leeuwen 2007a), whereas the solid line represents the fiducial relation between the Hipparcos magnitude and the standard parallax error. Large red circles correspond to stars redder than V − I = 2.