Left: example map showing sources detected in the image of the host of PTF10aagc. The SLSN host is shown in green, while objects within ±1.25 mag from the host are shown in blue. All other sources are shown in red. The masked regions appear clearly as white empty bands. In the random objects test, only the companions of the blue sources are counted. Right: example map where the coordinates of all sources in the left panel have been re-generated randomly for an iteration of the random coordinates test.