Hess diagrams for the distribution of the uncertainties in the source magnitudes as a function of the source magnitude for the J-band (top), the H-band (middle), and the K_s-band (bottom). The color scale shows the number of objects in 2D bins with a size of 0.025 mag on the x-axis and 0.002 mag on the y-axis. In all bins with fewer objects than the lower limit indicated at the bottom of the color bar, the individual objects are plotted by black dots.