Left: SDSS image (composite 3 colour image from bands i, r and g on log stretch scale) with SDSS contours at 3 times the rms noise after smoothing from bands z (white), i (cyan), r (red), g (green) and u (blue). The rms noise of each band before smoothing in units of maggies is 4.14 × 10^-2 (u), 1.44 × 10^-2 (g), 2.38 × 10^-2 (r), 3.82 × 10^-2 (i), 2.1 × 10^-1 (z). FIRST contours are shown in lime at 3, 5 and 15 times the rms noise. Right: SDSS image (composite 3 colour image from bands i, r and g on log stretch scale) with smoothed SDSS contours from the composite image at 3, 5, 10 and 30 times the rms noise after smoothing. Letters mark the positions of resolved galaxies. All smoothing is performed with a Gaussian kernel of standard deviation 1.72′′. This area is shown by a dashed yellow rectangle in Fig. 1.