The number of wavelengths required for consistent simulation seems to depend on the size of the raindrop, with many wavelengths being needed for small drops.  As the computation time decreases for smaller drops, it is possible to increase the number of wavelengths used for small drops without incurring a dramatic penalty in computation time.

Although MiePlot users can specify the number of wavelengths to be used in each simulation, this approach does not produce the best results for Lee diagrams which plot how optical phenomena vary with drop size.   To overcome this problem, the number of wavelengths can be set to "High", "Medium" or "Low".  In such cases, MiePlot varies the number of wavelengthsas a function of drop radius - as defined by the 3 functions shown in Fig. 1 below.

This feature can be used for all calculations involving multiple wavelengths- not just for Lee diagrams.