I’ve nearly finished this portrait painting. Its had 5 glazes over the initial underpainting. This picture shows the grisaille, the first glaze (which I filmed and is on youtube) and then the 5th glaze which is almost the last one. I still intend to go over the hair and background again amongst other things. The background was a dark green the glaze before this! It still shows through and gives it a nice depth. The lovely thing about working in this way is that everything can change with just one glaze. This portrait has been through many stages while painting each glaze. Sometimes I misjudged a colour or hue or the values of light and dark weren’t right. In each case I was able to correct the painting in the following glaze, either lightening or darkening.
I love painting highlights in a portrait so I guess I overdid it somewhat and the lightest light ended up too bright by the 4th glaze, but in the latest glaze which you can see here I went over the whole portrait again with a darker glaze just to soften it a little. In areas where it was too dark again I just used a dry brush to pick off the paint and continue blending. I can always keep adjusting a portrait at a late stage if the client commissioning the portrait feels there is something that needs changing.
It is surprising just how close to the original grisaille the painting is, even when its possible to see how much refining and drawing has gone into the portrait over all the glazes. Its strange to see later very finished versions of a portrait where the grisaille is like a ghost, still very present but disguised under veils and glazes of colour. The grisaille functions like an anchor that holds the structure of the portrait in place, and many many changes can occur but the painting is still held firmly together by the initial drawing. Its the main reason I started learning how to paint using the grisaille method.
I always use the same mixes when I paint portraits using the grisaille method. All my glazes start with various quantities of the same colours: Alizarin Crimson, Cadmium Red, Raw Umber and Sap Green (a warm Sap Green). All the later glazes are mixed with these colours but with other additions, like Ultramarine Blue to cool it down, a bit of Titanium White to make a velatura or semi opaque glaze, some Cadmium Orange.. but always hovering around the same original mix. Of course this depends on the commission and the sitter having their portrait painted.