Spatial distributions of different populations of the centre field as two-dimensional histograms with 15″ bin size overlaid on the DSS2 red greyscale image. Top and first row: selections based on the F090W – F200W colour magnitude diagram and comparisons with isochrones as shown by two-dimensional histograms. Third row: histograms show individual stars selected based on their excess. Bottom row: histograms showing stars that fall in two or more selections. A scale bar of 2′ is shown in the first panel.