- Another critical aspect is the sensitivity towards power level settings that determines the efficiency under experimental imperfections such as RF inhomogeneity and fluctuations in tuning and matching during long experiments. A more forgiving method towards power level mismatch is also easier to setup without long search for optimal conditions. Figures ) and 2(D) depict the behaviors of CP and the OPTIANS as a function of RF amplitudes on the two channels, i.e., 𝜈 .