In a multidetector SEC system it is necessary to match the outputs of the detectors that sense eluant concentration with those that are molecular weight dependent. There are several methods to accomplish this. The most common is to determine the interdetector volume or time difference between detectors. The difficulty with this technique is that with detector systems where the column eluent is split, the interdetector time difference Varies with solution viscosity. Two new techniques were implemented on a high temperature SEC/DRI/LALLS/VISC system which take into account changes in solution viscosity due to high molecular weight polymers. Both techniques use calibration curves of hydrodynamic volume versus elution volume for the different detectors to determine the "instantaneous" time difference between the detectors as it varies with solution viscosity. Either method provides the correct interdetector time lag information. We note also that in multidetector systems the configuration of the detectors should be such as to maximize solvent flow rates through each detector and hence to minimize band broadening effects.