Optimised solutions for all five artificial binary systems. From top to bottom: model systems as referred in the text and Table 1, from B5+B7 to F2+G0. Left column: binned model (red) versus noised and binned ‘observed’ (dark grey) light curves with the residuals beneath. Note: residuals inside eclipses appear more noisy due to eclipse over-sampling during the binning process. Middle and right columns: disentangled spectra of both components (dark grey) and best fit synthetic spectra (red) in two wavelength regions; there is a wider range with the H_γ line (middle) and a zoom into the region with the magnesium 4481Å and the helium 4471 Å (for hotter stars) spectral lines (right). Disentangled spectra of the primary and secondary are shifted vertically for better visibility, residuals are shown beneath.