True colour images, created using the 3.6, 4.5, and 8.0 μm Spitzer/IRAC mosaics of groups HCG16, HCG54, HCG79, and HCG92, respectively. The green and red contour maps are the 250 μm Herschel/SPIRE and the VLA/HI moment-0 maps of the same groups. The five contours correspond to 3, 5, 7, 9, and 20σ. In the bottom right corner of each panel, we present the size of the SPIRE 250 μm and VLA band beams, respectively. The RA and Dec scales of the axes are in J2000.0 coordinates.