Linseed: now I have that portrait at a stage that makes it look likely to work in the end. After a three hour session before lunch using some thin and other thicker layers of over-painting, all the loose elements in the face are working together. It now needs to stand for a few days before the next layers go on.
Here is an excellent site that discusses portraiture for the oil painter Oil-painting-techniques. Some of the info could reasonably be converted to colour tables, but the general tone of the page is good for the intermediate painter.
I’ve learned some important stuff since starting these portraits, though I did suspect it before. It’s vital to continue "prep" after the final painting is started. It’s a time to work out those colour problems, compositions or details that arise. "Prep" is the wrong word then.
I love that tiny sketchbook, it’s only A5, but the paper is the right weight and texture. It could do with a weaker base colour perhaps, but I’ll adjust to that.
I bought another A5 book today mainly for graphite.