bulge masses are hard to measure

On a low-research day I prepared and gave a short coffee talk at MPIA about our work on the insane-robot censored-data project (with Richards, Long, Foreman-Mackey, and Bloom). After me Ronald Läsker (MPIA) spoke about galaxy bulge-disk fitting of two-dimensional galaxy images and the insanity of it all; what you get for the bulge mass is a very strong function of how many components you include and which ones you think of as being bulge. He finds that adding more galaxy components can increase or decrease the inferred bulge mass by factors of a few in typical cases. So unless someone has a full kinematic decomposition, don't believe a bulge mass uncertainty that is more precise than a factor of two! In general, the problem with bulge measuring is in the interpretation of fits that are otherwise extremely valuable for photometry and other purposes; if we just think of the amplitudes of the components as uninterpretable latent parameters, they don't cause any trouble at all, and you still get good colors and magnitudes.