Upper panels: comparison between the behaviour with age of the (V − R) and the (J − K) colours extracted from our model spectra (based on Padova00 isochrones) and the same colours from the MILES photometric predictions (see http://miles.iac.es; Vazdekis et al. 2010, 2015). The dotted lines delineate the MILES photometric predictions and the solid ones the colours calculated from our SSP model spectra. The different colours and symbols represent three different metallicites (see legend). Lower panels: visualization of the absolute differences between the colours measured from our model spectra and the photometrically predicted ones.