At the Microscopy and Microanalysis 2003 meeting, a member of the audience in one talk sharply criticized a speaker of a talk for his use of a Savitsky-Golay (S-G) digital filter for smoothing Electron Energy Loss Spectroscopy (EELS) data. The statement was made that the digital filter would decrease the resolution of the peak, i.e. widen the width, and that all digital filters do that, including the Top Hat filter. In support of this statement, he said to consider what would happen if the

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... r were applied to a Dirac delta function. I knew that his argument was not correct, but I didn't think of the reason until later. This interchange was on my mind because I was familiar with both of these filters due to implementing both the Top Hat and the Savitsky-Golay filters into my "Beerware" program, EELS-PLOT.