Surface flux profiles of NGC 1275 are shown by black lines. The solid and dashed red lines correspond to the best-fit double-Sérsic profiles and the uncertainties as in Fig. A.1. These profiles are subtracted from the surface flux profiles of NGC 1275, yielding the green data points. For the ICL, the residual background constant is estimated by averaging the outermost eight of these points, with that constant set to zero in this figure. The green shading represents the uncertainties on the residuals. For the ICGCs, the background is set to the number density of the outermost data point. The grey (blue) shading represents the uncertainties from the background surface flux profiles of Abell 2764 (the Perseus WISE 12 µm map). Both uncertainties combined and flipped result in the black error bars of the surface flux profiles of NGC 1275. One count in I_E (Y_E, J_E, H_E) corresponds to 27.4 (25.1) mag arcsec⁻².