Selection of disk candidates obtained from a combination of four different IR CCDs. The upper left panel shows the W123 CCD selection (W1 − W2 versus W2 − W3), the upper right panel the W124 CCD selection (W1 − W2 versus W2 − W4), the lower left panel the HKW2 CCD selection (H − K_S versus K_S − W2), and the lower right the HKW3 CCD selection (H − K_S versus K_S − W3). In each plot, the blue circles show sources selected as disk-bearing and the orange crosses are disk-less. The borders are the dashed, black lines in each diagram. In each plot, the extinction vector is shown, scaled to a value of A_KS given in the plot above the extinction vector.