Pseudo-colour mosaic image of all observations showing 0.4–1.8 keV (red), 1.8–2.8 keV (green) and 2.8–10.0 keV (blue) rates corrected only for the residual proton background (top panel), and central part of the same image corrected for all identified background components (bottom panel). All images are presented in equatorial coordinates shown in a grid in the top image. The scale of the uncorrected image has been adjusted to emphasise the contamination by stray light (mostly seen in blue) and extended emission towards the western part of the remnant. Note that the stray-light contamination is even more severe in individual observations as the location of the single reflection arcs is sensitive to the pointing of telescope.