The painting was a lot of work and took every day. My original deadline was one week short of the absolute final deadline but in the end I had to push it!
The underpainting came next and I decided to paint lots of detail. In underpainting I've often wondered about just how much detail to paint. Generally the more detail the better. In fact whenever I've painted with lots of detail I'll add even more detail later and the results are fantastic. However, there are some occasions when it's inefficient, with fine details like eyelashes or thin tree branches best painted later instead of once in underpainting, and then again later.
I started with the leaf...
Then moved over the painting from top to bottom, moving in tiny sections, each taking a day...
Underpainting colours must be permanent, opaque, fast drying, and dull in colour. Fortunately many colours fit this. Some like cadmium yellow have the opacity but are not permanent enough or dry too slowly. Transparent colours like ultramarine are not appropriate. The best are titanium (or any) white, mars (or any) black, yellow/red ochres, nickel yellow, chromium oxide for green. The only blues that are appropriate are cobalt turquoises which are permanent enough but only just opaque enough. They will do.
That layer took ten days. When complete I glued the brass to the cabinet and attached the hinges. That was done.
Then, after a few days to dry, the glazing. Glazing should use transparent colours, or opaque, or any others you like. The foundation of the painting has been set by now. Transparent layers will darken, as light is absorbed.
With a day left until the deadline, the cabinet was complete..
Here is the finished painting, The Paranoid Schizophrenia of Richard Dadd. Oil on panel, 400x400mm.