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Abstract

Three of the selection methods used with regularized data inversion were tested with dynamic light scattering data from a binary mixture of polystyrene latex particles. The three methods were the F-test (the standard method of CONTIN), the stability plot (one of the methods used with ORT) and the L-curve method. Two experimental situations differing in the scattered intensity were studied. The first was that of low mean count rates, where the random photon detection noise was dominant; the second was that of high mean count rates, where the non-random intensity fluctuation noise prevailed. The F-test proved to be very sensitive for non-random statistical and systematic errors, and then yielded too weakly regularized solutions associated with complex and poorly reproducible size distributions. The stability plot and L-curve methods, on the other hand, proved to be largely insensitive to these kinds of errors in the data and yielded reliable results, as concluded from a comparison with the size characteristics of the particles determined with electron microscopy.