The polarized emission (in units of mJy beam^-1 RMSF^-1) in the field of A2255 at 85 cm is shown with (left panel) and without (right panel) total intensity contours on top. The frames refer to a Faraday depth of φ = −24 rad m^-2 and have a noise level of about 30 μJy beam^-1. The noise level of the total intensity image is  ~0.1 mJy beam^-1. The contours of the toal intensity image are –0.3 (gray), 0.3, 0.6, 1.2, 2.4, 4.8, 9.6, 20, 40, 80, 160 mJy beam^-1. The resolution is 54″ × 64″.