Colour−magnitude diagrams of the five clusters in our sample with the location of our target stars: MS (filled circles); RGB (crosses), RC (stars), and discarded stars either from their position in the colour−magnitude diagram or by low signal-to-noise ratio spectra (open circles). The best photometries available in the literature have been used, although this implies different filter combinations since similar quality photometry for all the clusters in our sample is not available in the same bandpasses.