Extract from time series vs. time for F6 stars, different OGS configurations (from top to bottom) and for three temporal coverages: 8 h (left-hand side panels), 5 days (middle panels) and 50 days (right-hand side panels), smoothed over 1 h. For the 8-h coverage, ten examples corresponding to adjacent nights are superposed (each section of the RV time series is represented by a different color). For the two other coverage sets, the black line represents the full resolution time series (smoothed over 1 h) and the red circles are the selected points used in the analysis (one point per day).