Portrait in oil, II

Another portrait. This painting was done about three weeks ago. I just finished another one two nights ago, but I have to wait till that dries before I can scan it. I've been trying to stay loose, with no drawing. I work in the shape with a 1" or a 1/2" filbert. Working in a limited palette of Burnt Sienna, Cobalt Blue, Cadmium Red, Cadmium Yellow, Crimson Red, and Zink White. Same as a couple of posts ago where I had the woman portrait. I have been forcing myself to work in a limited palette to first, stay simple and try to work on my technique, application, value, shape, etc. I tend to get lost very quickly once I start trying to add too many colors. I recently added Ultramarine Blue to my palette as the colbalt and cerulean blues don't have the intense deep blue that I need sometimes. I was also able to mix a pretty convincing black with just Burnt Sienna and Ultramarine Blue. I'm still sticking with Filbert brushes, but I think I want to try flat square brushes.