Slope distributions for different reddening relations in IC 342. For each distribution, we show the 68% confidence interval of the median [CI(Mdn)] and the standard deviation (SD). Dashed lines mark the medians of the distributions (red), values predicted by the F99 extinction curve (blue), and values predicted by the CCM89 extinction curve (green). The median values found in the MaNGA main sample are indicated by the dotted purple lines.