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(A), (B) The stray light corrected and uncorrected images of the ND filters in the filter wheel, respectively. (C), (D) The corrected and uncorrected images of the ND filters alone, respectively. (E) A plot of the measured and corrected ND filter values versus the manufacturer reported ND values. Discrepancies begin to arise at an OD of 2, with the correction absolutely needed beyond an OD of 2.
