The following graph portraits the effects of delta scaling on a layer with

optical depth tau=1
single scattering albedo of w0=.9
and various asymmetry parameter values from 0 to 1

The first couple of curves are for consecutively scaling the optical properties with a scaling factor of f=g**2.
Then a scaling to fixed asymmetry parameters, for g=.65, g=.5 and g=0

In the following we test the gmax approach on the infamous I3RC cumulus cloud scene. Here with the Tenstream with 3 direct and 10 diffuse streams and 60 degree solar zenith angle. Relative root mean square error of fluxes at the surface and of atmoshperic absorption.

The visible trends are that less deltascaling(gmax==.65) gives better results for direct radiation and slightly also for atmospheric absorption. Stronger deltascaling however leads to better diffuse radiation at the surface. However, the net radiation at the surface is the same ( Eup = (Edir+Edn)*constant_surface_albedo ), irrespective of the deltascaling method.

The script for plot can be seen here.