In figure (b), the 3D perspective view of the BRDF is represented. Thanks to a cross-section tool in the software, you can easily focus on an area of interest, such as the specular peak.
In addition, the Synopsys Mini-Diff V2 software provides an RGB tool that provides color information with an RGB representation, as well as the CIE color space (L*a*b) coordinates, which can be very important for this application. You can then extract red, green, and blue curves in one plane (shown in figure (c) above) to study the color. Notice, for example, that the red curve presents a lower level of scattering than the blue or green curves, which is expected.