The takeover by a SN light curve would also result in a dramatic reddening of the afterglow colours. ANTU unit telescope.
North is up and East is to the left.
Same image as above with 3 stars subtracted. Also a point source has been fit and subtracted from GRB 990712. There are no residuals after the stars but significant residuals after the GRB 990712 despite it being fainter. This is evidence that the object is extended and hence contains a significant contribution from the GRB 990712 host galaxy. Zoom-in on a smoothed version of the PSF subtracted image.