An example snapshot of a realistic cluster model after 12 Gyr of evolution. On the left, we show a synthetic HST observation of the cluster, computing using the stellar positions, effective temperatures, and radii (via the Fresco package; Rieder & Pelupessy 2019). On the right, we show the V-band surface brightness profile (at a distance of 5 kpc) and 1D velocity dispersion for the cluster, calculated using the cmctoolkit package (Rui et al. 2021a).