Radial velocity curves for two well-known extra-solar planets, TrEs-2b (left panel), and TrEs-3b (right panel), derived from the early measurements taken during the CAFE commissioning run. Red circles represent the derived values for the radial velocity. The black solid line represents the theoretical curve assuming the simple expression , where a is the semi-major axis, P is the orbital period, i is the orbital inclination, and φ is the orbital phase. The shaded region was calculated by error propagation of the values in the previous expression. The lower panel shows the residuals for the fit.