Residual image in the I_E field of the Perseus cluster (after ICL subtracting): The centres of elliptical (E) galaxies are marked with red dots, S0 galaxies with green dots, intermediate types between S0 and spirals with cyan dots, and spirals with dark blue dots. Coloured circles, centred on the central elliptical galaxy NGC 1275, indicate the average projected distance for each morphological type.