Left column: the “true color” images, created using the 3.6, 4.5, and 8.0 μm Spitzer/IRAC mosaics, of the 10 galaxies discussed in Sect. 4.3. The images are aligned northeast, and they are 1.5    ×  1.5 arcmin in size. Right column: contour maps of the same fields observed in Ks-band with WIRC at the Palomar 5 m telescope. The five contours correspond to 3, 5, 8, 10, and 30σ. Since all images had similar exposure times the noise was σ ~ 19.6 mag arcsec^-2. For two galaxies not imaged with WIRC, HCG68a and HCG100a, we used the shallower Ks-band data from 2MASS (σ = 15.7 mag arcsec^-2).