Polarized intensity after the application of the RM synthesis and the removal of the positive bias obtained between 900 MHz and 1.4 GHz. The resolution is 13″. The zoomed images around the bottom left image are centered on the five polarized cluster sources. For each of them, we show the optical image from the Fornax Deep Survey in gray scale and the total intensity contours starting from 3σ, whose value is reported in the bottom right corner of the image, and increasing on a logarithmic scale.