Hi, I tried to set the limits of the colorbar using set_zlim as below... fn = "RedshiftOutput0002" pf = load(fn) pc = PlotCollection(pf,center=[0.5,0.5,0.5]) p = pc.add_slice("Density", 0) p.set_zlim(1e-31, 1e-30) pc.save() But I keep getting a plot with colorbar ranging between (1e-31,1e-28). I can't see what I am missing. shankar