Colour scale: reconstructed 512 × 512 image of Cygnus A at 151 MHz (with resolution 2.8′′ and a pixel size of 1′′). Contour levels (Toggle contours) are [1,2,3,4,5,6,9,13,17,21,25,30,35,37,40] Jy/Beam from a 327.5 MHz Cyg A VLA image (Project AK570) at 2.5′′ angular resolution and a pixel size of 0.5′′. Most of the recovered features in the CS image correspond to real structures observed at higher frequencies.