It has been a long time since I have worked on a portrait with oil. I did this in two 3-hour sessions working in alla-prima (wet-on-wet) using a 50/50 mixture of Grumbacher Stand Oil and oderless turpenoid as my medium. This combination is said to mimic mediums used by the old masters, whatever that means. Either way, I really like that it dries quickly and retains some nice brush strokes. I did use Liquin during the initial sketch, but I see could have use the stand oil mixture from start to finish. I will try to take progress shots on my next portrait. I may do a post on different mediums and/or other tools and tips if anyone is interested in learning more about oil painting.