Left: RXC J1053.7+5452 WSRT 1382 MHz image. Contour levels are drawn as in Fig. 1. Black dotted lines indicate the integration area for the flux measurement. Right: RXC J1053.7+5452 X-ray emission from ROSAT in orange. The original image from the ROSAT All Sky Survey was convolved with a 225″ FWHM Gaussian. Solid contours are from the WSRT 1382 MHz image and drawn at levels of  [1,2,4,8,...]  × 4σ_rms. Dashed contours show the galaxy iso-density distribution derived from the SDSS survey. Contours are drawn at  [1.0,1.2,1.4,...]  × 0.25 galaxies arcmin^-2 selecting only galaxies with 0.05 < z_phot < 0.1. Discrete sources embedded in the diffuse emission are alphabetically labeled, see Table 3.