Residuals between the observed and predicted stellar position for the cameras of the northern station for an image taken on July 11 2016 00:05:08 UT. Each panel shows the difference in the observed and predicted x,y positions for approximately 1000 stars used in the astrometric solution. Typical standard deviations in both the x and y residuals are ~ 0.2 pixels for the north, east, south and west cameras and ~ 0.3 pixels for the zenith camera, probably due to stronger vignetting.