To get IDL colors to 'work right' (i.e. a colortable has 255 colors etc), put this in a startup file:
device, true_color = 24, retain = 2, decompose = 0red = [0,1,1,0,0,1]green = [0,1,0,1,0,1]blue = [0,1,0,0,1,0]if not strcmp(getenv('DISPLAY'),'') then $ tvlct, 255*red, 255*green, 255*blue