Friday, October 22, 2010

...a little more!





Here's a progress shot of the painting as it stands now. I've continued modeling forms on Lisa's face, and I'll begin shaping her hands shortly. The sleeves on the dress will be underpainted all the way up to where they tie onto the bodice of her dress, then layers of black silk gauze will be painted over the top of the finished upper sleeves. I'm thinking it'll be good to lay the color in on the sky before I do much painting on her hair, and may start to indicate the mountains in the background at that time. After the paint on her face dries, I'll begin layering glazes of color into the darker shadows on her face. Then, a layer of white with a little vermillion will be put over the modeling, letting a hint of the undercolor show through. Glazes of color to deepen the flesh tones and model things further will finish the face. There are areas in the shadows on the original where researchers estimate there are 40 layers of glazes present!

I've been reading and re-reading Daniel Thompson's great book on Tempera painting and gleaning much information on possible technique from that.

Saturday, October 16, 2010

Quick Peek


Here's a quick update with a new technique I was trying out today. I started to model the forms of the face with non-diluted paint scumbled on with a brush with almost no paint on it. This allowed me to paint on very subtle shading with much more control than trying to model forms with a brush more fully loaded with paint. It also allowed me to easily soften edges wherever needed. This technique is in line with Leonardo's putting down extremely thin paint layers.

But, again, I'm not allowing the panel to dry between sessions, so there are areas that I smudged in doing this layer of work. I'll be letting the panel fully dry now before proceeding!

Oh! I also uploaded a pretty large image this time so the detail can be seen more easily!

Thursday, October 14, 2010

More Progress




This is Mona as she sits now, so to speak. I've added a wash of yellow ochre over the entire panel, as I believe from analyzing unfinished works by Leonardo that the yellow in his underpainting doesn't seem to be aging of the paint layer, but an imprimatura wash of yellow. I've also done some washes of thin black over many areas to tone them darker prior to painting detail in the underpainting. I do a little, then let the paint dry a few days, then do a little more. I've also done plenty of work with a fan blender to help smooth transitions between tones. There are a couple of spots where I didn't let the underlying paint dry enough, and in my haste, smudged the underpainting. Once the darks are established, I'll lay in the light tones as a white lead and vermillion wash over the flesh areas, and then begin adding color.

Friday, October 8, 2010

Gesso Formula

I started off the blog thinking that perhaps getting too bogged down in what I thought were the more mundane details of the project would cause people to tune out. But, Kathy had asked about some specifics, so I thought I'd address that request in a regular post.

My gesso formula was based on measurements given in Ralph Mayer's book, The Artist's Handbook of Materials and Techniques. I used in my final formula, 2 3/4 oz. of Italian rabbit skin glue, from Natural Pigments, and 1 qt. of water. I put the glue and water in a double boiler and let it hydrate overnight. The next day, I melted the glue over low heat on the stovetop and added an equal volume of Italian gesso (calcium sulfate), also from Natural Pigments. I added the gesso by sifting it slowly into the melted glue mixture and letting it wet out before adding the next bit. Once the gesso was in the pot and all hydrated, I stirred carefully with a small whisk to blend it all together. That created the gesso grosso, which was laid on the panel in a somewhat thicker layer and smoothed with an offset spatula or a wooden slice (see Daniel Thompson's book The Practice of Tempera Painting referenced below). For gesso sottile, I added a bit less gesso so that the mixture was like heavy cream. The gesso sottile was brushed on and then smoothed with a spatula. Each coat was allowed to dry to the point of having no surface sheen, then the next layer added. I put on 5 layers of gesso sottile. Oh, and all the gesso was strained through a double layer of cheesecloth before application, and kept warm in the double boiler between coats. The finished gesso surface is probably a little harder than it needs to be, but I thought it would be preferable to err on the harder side than make the gesso too soft.

My reference for gesso application was mostly from Daniel V. Thompson's great book on egg tempera painting, The Practice of Tempera Painting, Materials and Methods.

Once the gesso was totally dry (I gave it a week), I sanded the panel smooth and scraped the surface (with a steel scraper from Natural Pigments) to a slight sheen. Then it was sealed with a very dilute mixture of denatured alcohol and clear shellac, and was ready to prime. For the priming, I used white lead ground in walnut oil to a fairly thick paste, and thinned it to a nice brushable consistency with gum turpentine. The priming was applied with a wide sable brush, then smoothed with a fan blender. The surface dried practically free of brush strokes. Some authorities suggest letting the panel season for 6 months to a year before beginning work, and others say there's no empirical evidence to support that practice. I opted to start with no wait period. Because I'm impatient like that.

Thursday, October 7, 2010

Test Panel Underpainting



This is the test panel after a little more progress on the underpainting. I softened many of the lines from the initial burnt umber draw-in, feeling they were too definite to allow for much sfumato type modeling to happen over them. On the hero panel, I've decided to modify this approach and do my initial block in with pale gray washes, then selecting which areas to sharpen with an umber line and a fine brush. I'll add a richer ocher wash over this entire panel, I think, and build shadows from there. In the intermediate steps, I'll lay in opaque colors in some areas and finish them by modeling glazes over the top to bring out depth and form.

Of course, a certain amount of this is speculation, and I'll make appropriate adjustments as I go.

Sunday, October 3, 2010

Test Panel is Underway!



Well, after almost 10 months of waiting and prep, today I transferred the drawing over to the test panel and officially began applying paint to panel. I used a tracing of an enlarged infrared photo of the Mona Lisa as the basis for the cartoon I used to transfer onto the panel. I rubbed the back of the tracing paper with charcoal, and taped the cartoon in place and transferred the drawing to the panel. I then used a fine brush and burnt sienna oil paint and permanently drew the lines onto the panel. I'll let the paint dry, then wash off any remaining charcoal. I've uploaded a picture of the panel as it looks now.

Which leads me to the next group of pictures.



I decided to post these to point out the differences in technique between my preliminary panel and the way the paintings will progress on the real panels. The painting will be done by doing a more traditional approach than what I did for my preliminary panel. Tradition dictates that a painting is done by first doing a complete monochromatic underpainting, then layering glazes of color over the underpainting. The preliminary panel, which is the panel upon which I tested paint formulations, was done alla prima, as the sequential photos show. I used mostly 1" disposable brushes to do the preliminary painting and of course will use more refined brushes for the final piece.˙Anyway, the progression shown above is, from left to right, the preliminary panel with various types of gesso treatment applied; the panel with rough planes blocked in (testing oil colors I ground); refining the rough paint-in; And the panel as far as It was taken. The oils were used both thinned with walnut oil, and made into a glaze using sanderac varnish. All tests were suitably successful for me to feel confident moving on to the final panels

Sunday, September 26, 2010

Panel Prep Is Nearly Complete!

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!