Example galaxy extinction curve and corresponding mock observation. The extinction curve is shown in the first column of the figure. The total extinction curve (grey) is presented along with the contributions from graphite (cyan) and silicate (magenta) grains, each shown with two different size distributions (dotted lines for small grains and dashed lines for large grains). The MW (Fitzpatrick & Massa 2007) extinction, SMC (Pei 1992) extinction, and Calzetti attenuation curves are also included for comparison. The grain size distributions for different grain types are shown in the sub-panel, with the MRN (Mathis et al. 1977) slope indicated by a yellow dashed line. The spatial distribution of the DTM is shown in the second column. The corresponding mock image, created using SDSS g, r, and i bands for RGB, is shown in the last column.