Radial colour profiles (solid non-horizontal lines) of the BCG+ICL. The upper (lower) panel shows the Y_E − J_E (J_E − H_E) colour. The dashed lines represent colours measured in six different sectors. The colour uncertainties, shown by the shaded areas, are propagated from the background uncertainties (see Appendix B). The horizontal lines are Bruzual & Charlot (2003) models at a fixed age of 10 Gyr and different [Fe/H] metallicities (as labelled). The hatched area indicates the region with uncertain colours due to persistence residuals.