I thought I'd post a few pictures as the panels near completion of the gesso/surfacing/priming phase, and are nearly ready to transfer the cartoon onto to begin the painting(s)! Below is a shot of the gesso sottile on the panel. This is the fifth layer of gesso sottile, applied with a brush and leveled with a scraper.
As you can see, the surface has lots of irregularities that need leveling. After the panel dried, I sanded it smooth and scraped the final surface to eliminate any marks left by the sandpaper. That smooth, flat surface was sealed with a dilute mixture of clear shellac and denatured alcohol and allowed to dry, then a thin layer of lead white priming was applied. I also applied a second coating of lead white to the test panel. In the picture below, you can see the panels side by side. The panel on the left is the test panel. (Note the uneven surface...this is a result of having NOT put a sealer down before the walnut oil in the lead white came in contact with the surface. The hero panel on the right has a much more uniform finish.
Now, the panels will dry at least a week. once the panels are both dry, I'll likely do one last layer of priming, then I'll transfer the cartoon onto the panels and begin painting. The cartoon wil be rubbed on the back with powdered charcoal and traced onto the panels, then redrawn with umber oil paint. The picture below shows the cartoon taped in place over the test panel. You can see the (drawn) edges of the real painting, and how they align with the frame and panel beneath. I'm not convinced that the top edge is correct in my tracing, and have adjusted it on the final cut of the panel and the cut of the frame.
The image of the painting I liked for my cartoon was an infrared shot. It seemed to show more details of the piece that are usually hidden in shadow, such as the form of the entire chair Lisa is sitting in, and the structural elements of the parapet behind her. There's also a lot of detail in her figure and dress that isn't easily deciphered in other photos of the painting.
After the priming dries, I'll get pictures up of the work as it progresses ASAP!