Friday, October 29, 2010

Again With the Progress!

The above picture shows more modelling to Lisa's face. I've begun adding white lead over the underpainting to see how it softens and blends tones to further create Leonardo's sfumato effect. You can see on the right side of the face how the tonality changes and softens from the translucent overlay of white on the umber underpainting.

I've also found a fantastic article on the Musee Galileo site that analyzes Leonardo's Adoration of theMagi, which he left unfinished. The article shows pictures taken with with a multi spectral camera as well as other images, and sheds further light on how Leonardo prepared his panels, and how he did his preparatory drawings and underpainting. There's also evidence that much of the umber colored paint layer was done at a later date by another artist. Have a look at

What this means is that I'll make adjustments on the hero panel by doing the underpainting using lamp black on the white priming, and I'll lay in the sky fairly early, as Leonardo apparently did on the Adoration. (I'll be blocking in the sky on Test Mona on the soon side, too.)

But for now, it's Halloween weekend, and I'll be reprising my Dr. Zaius costume at a few parties!

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