Images of gas density and stellar distribution at different times for different maximum grid resolutions (higher refinement level n corresponds to finer grid resolution). Each row corresponds to a level; each column, to a simulation time (1.5 t_ff, 3 t_ff, 4.5 t_ff). The ionization fronts are marked with cyan lines. Stars are black dots; massive stars are red, with sizes proportional to their masses. In each panel, the notations are as follows: (bottom left) physical scale; (bottom right) the mass of the most massive star, total stellar mass, and number of stars; (top left) model label; (top right) simulation time. The color scale represents the gas density in grams per cubic centimetre.