The backgrounds oilpainting process

These are some photo's of my backgrounds oil painting process. The third image is a rough black and white (and 1 colourtone) digital sketch that I use to make my black and white underpainting on canvas (the light I will ad digitally to the final painting). The second image is the underpainting that I've made with acrylic paint. This gives me an idea of shading and contrast. As an example for colour I use the visual that I've made for my postcard. Normally this would be a rough colour sketch. The first image is a photo of the first layer of oil paint. The next step is to add detail and more shading and dept in the second layer of oil paint. To be continued...