Bringing light to galaxy formation simulations

Models of galaxy formation ultimately aim at reproducing the _observed_ properties of galaxies. We report on work in progress to predict luminosities, colours and morphologies of field objects of various masses through N-body + Smoothed Particle Hydrodynamics simulations. We describe our method, illustrate the effects of varying the star formation assumptions, show some preliminary results, draw encouragement from their strengths as well as lessons about what improvements are most needed.