Absolute

Absolute calibration is also known as Triple Detection (or TDA for short) although these days we often use 4 or 5 detetcors.

It requires a proper laser light scattering detector in addition to a mass detector and the Intrinsic Viscosity  detection.. in return you have to calibrate only once and you gain in the detail in the distributions.

1. The light scattering detector provides a direct measurement of absolute molecular weight and eliminates the need for column calibration.
2. The viscometer detector provides a direct measurement of intrinsic viscosity or molecular density, and allows the determination of molecular size,  conformation and structure.
3. Concentration is measured as usual with an RI or UV necessary for the determination of both molecular weight and intrinsic viscosity.