NGC 5128 CMD for all four CCD quadrants combined. Three rectangular sections are shown, two of which are dominated by contaminants to the RGB CMD. The cleanest sample of RGB stars in the halo of NGC 5128 are found in the lower right section drawn on the CMD. Sources brighter than the TRGB at I₀ = 23.9 (Harris et al. 2010, we have corrected for extinction) are field stars (upper section) – we justify this cut in Fig. 9. The lower left section (with (V − I)₀ < 1.5) is dominated by unresolved background galaxies which thus appear as point sources. Justification of the choice of (V − I)₀ = 1.5 for the break between background galaxy dominance and RGB dominance of the source counts can be seen in Fig. 11. Error bars for magnitude and color are indicated on the righthand side.