The result of increased opacities due to heavy element formation in kilonovae.  The left plot shows the expected light curves for Fe-like opacity (i.e., supernova-like): a peak time scale of a few days and most of the luminosity is coming out at (redder) optical wavelengths.  The right plot shows the significant difference when incorporating opacities from r-process elements.  The time scale to peak of the bolometric light curve is significantly longer (~ 1 week).  And the transient is significantly redder, as radiation is reprocessed to longer wavelengths.  From \cite{Barnes2013}.