Top panel – HST-NICMOS H − K color image (mag) reported by Marconi et al. (2000). The Spitzer-IRS SH grid is overlaid to show the difference in resolution and the different orientations of the fields of view. Bottom panel – Foreground screen extinction A_V(H − K) estimated from the H − K color image at the resolution of the IRS/SH map. The SH pixels that cover less than 400 pixels in the H − K image are shown in dashed lines.