This under-painting of Aurora is on oil primed linen, 14”x32”. I have found that working large forces me to do a more thorough job on each form before moving ahead. This painting has a grey toned ground about value number 3. (I wanted the background to be a darker value without resorting to a thick layer of paint for my wipeout.)
I transferred my drawing and went over the lines using raw umber mixed with quick dry white paint. I mixed up a neutral greenish tone that I wanted to serve as the background color (for other under paintings I have used raw umber.) I covered the canvas with paint and a little turpentine and then wiped it evenly with a rag before the model began posing. In the first twenty minutes I did a wipe-out of the lights with a rag focusing on the largest shapes.
I then went back adding white (this time it was a mix of lead white and quick dry titanium-- I have found flake alone to be challenging because of its transparency and with titanium alone it is hard to build up a thick paint layer and have subtle value variation at the same time.) I began with the local light and worked out from the middle to the edge of each form, working the white into the paint left from the wipeout. I worked the whole piece in several passes, adjusting the value and getting brighter and more detailed each time.
I added more of the base color to make areas darker when needed and to help transition out of the core shadow and soften the edges. I focused on the overall hierarchy of light, making each form feel fully lit and rounded, and keeping the connections strong between each form. I did not touch the shadows and plan to leave the background as is. I have found that if I touch the background after the initial wipe-out the paint is tackier and will remain uneven.