Redshift of the Cu-Kα line (in per cent) as a function of detector position over the mission lifetime in FF (left) and EFF (right) modes, after correcting for the average value. The range shown in the top-left of each panel is the XMM revolution. The shift has been measured in 1 × 20 pixel regions and a σ = 2 pixel Gaussian smoothing applied for display. Detector regions with a large uncertainty in a combined error map have been masked out.