than use one or the other of these set radii, in order to compare with the M$_{\mathrm{cold}}$ from the low resolution run we want to include all of the cold gas within r$_{200}$. Therefore, in order to estimate the cold gas within the virial radius of galaxies in the high resolution simulation, we separate the galaxies into low-mass galaxies with M$_{\mathrm{halo}}$ $<$ 2.5$\times$10$^{11}$M$_{\odot}$ (and therefore virial radii at or less than 100 kpc), high-mass galaxies with M$_{\mathrm{halo}}$ $>$ 6$\times$10$^{12}$M$_{\odot}$ (and virial radii at or greater than 300 kpc), and galaxies that fall between these two extremes. The two extreme cases are simple, and M$_{\mathrm{cold}}$ is either the gas within 100 kpc for the low-mass galaxies or within 300 kpc for the high-mass galaxies. For all other galaxies, we use the halo mass to determine the fraction of gas between 100-300 kpc that we will include in M$_{\mathrm{cold}}$, using M$_{\mathrm{cold}}$ = M$_{100 kpc}$ + (M$_{\mathrm{halo}}$/6$\times$10$^{12}$)$\times$(M$_{300 kpc}$-M$_{100 kpc}$). With these definitions, M$_{\mathrm{cold}}$ is consistent between the low- and high-resolution simulations at $z$=1.

The luminosity of each stellar particle at each of the Sloan Digital Sky Survey (SDSS) five bands is computed using the GISSEL stellar synthesis code (Bruzual & Charlot 2003), by 