Illustration of the process followed to estimate the magnitudes of unresolved sources in the arc at 2 micron and larger wavelengths. The left column shows the raw data in each filter. The second column shows the template degraded to the resolution of the raw data following the process described above. The third column shows the difference Raw-Template. In this difference, the point sources are evident in all bands, while some are not so clearly visible in the raw data. Finally, the last column shows the residue left after fitting the point sources with the corresponding star shapes from Figure A.1. The residue has very little signal left, specially in the longest wavelengths. In all cases the template is the point source subtracted F150W image after degrading the resolution to the one corresponding to each band. The template is shown in the right panel of Figure A.2, and at its native resolution.