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Visual Magnitudes and the "Average Observer": The SS Cygni Field Experiment

Volume 27 number 2 (1999)

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Richard H. Stanton
217 Starlane Drive

Abstract

Results of the V-Magnitude Experiment - 1998, designed to characterize the vision of the "average observer," are discussed. Over 650 individual observations were analyzed, submitted by 63 observers worldwide. These data lead to summary conclusions in two important areas: (1) effect of star color on observed star magnitude, and (2) the range of observation scatter expected for observers using perfect comparison star sequences. Quantitative color response measurements for 48 individuals, when compared to the "average observer," show variations generally consistent with measured levels of observation scatter. Based on these data, a color coefficient value of b = 0.21 is recommended for translating Johnson magnitudes (UBV) into visual magnitudes (mv).