The spatial distribution of low (left) and high (right) variability stars for ARC (top) and PDC (bottom). Each has been subject to a random selection of equal numbers of stars per magnitude bin, before a random selection of 6000 for each panel was selected. The PDC panels show a slight tendency for the high variability sample to be more concentrated towards the galactic plane, whereas this effect is not significant in the ARC, suggesting it is more effective at removing contamination related systematics.