A three-color GLIMPSE image with logarithmic BGPS 1.1 mm dust continuum contours (from 90 mJy to 0.8 Jy) on our test region in the Hi-GAL SDP ℓ = 30° field. Red: 8 μm, green: 4.5 μm, and blue: 3.6 μm. This figure demonstrates the distinction between the IRDC and dust continuum population. Some dust continuum sources are mid-IR-bright, some are mid-IR-dark, and some have no IR correlation. The object in the center is particularly well-suited as a test case for this study as it contains both mid-IR-bright and mid-IR-dark dust continuum sources radiating as filaments on either side of a young HII region complex.