Estimated ESD values for a compound BSC composed of Faran-based particles as a function of scatterer distribution standard deviation at several center values (40 µm, 45 µm, 50 µm, 55 µm, and 60 µm). While it appears that all of the fits converge to a single value at broad distributions, it also appears that exponential fits offer the greatest ability to differentiate among the distributions (higher ‘contrast’ to distinguish between two broad distributions at two different center diameters).