A method of operating a quadrupole mass filter is disclosed. A first set of RF and resolving DC voltages are applied to electrodes of a quadrupole mass filter to selectively transmit first ions having a first mass-to-charge ratio (m/z). A second set of RF and resolving DC voltages are applied to electrodes of the quadrupole mass filter to selectively transmit second ions having a second m/z. Detection of the second ions is initiated after completion of a settling time. The settling time is determined in accordance with the relationship: Eq. 1, where ts is the settling time, (m/z)1 is the first mass-to-charge ratio, (m/z)2 is the second mass-to-charge ratio and A, B and C are empirically derived coefficients.