I recently taught a portrait workshop in Chicago, the subject of which was an
alla prima approach. This method, popularized in the 19th century by painters such as Sargent, Sorolla, Zorn, Whistler and Boldini, relies on producing a strong, gestural effect with the brush, that, paradoxically, aims to capture optical effects: soft and sharp edged-focusing, accurate hue and value relationships and a sense of quick-looking, as if the subject was seen at a glance.
In my own work I prefer to layer the paint, building cool, opaque layers over warm, transparent ones, and the painting is preceded by a detailed contour drawing.
Nevertheless, it is enjoyable to test oneself by attempting to capture a portrait in a single, quick oil sketch, with little preliminary work.
For this demo, my view of our model was a right-facing profile. I used a 14" x 11" canvas board, which I earlier covered with a medium-value
imprimatura of black & raw umber acrylic. Once dry, I began this oil sketch, which took about one hour, more or less.
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| Step 1: Sketching profile with charcoal |
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I quickly sketched out the model's profile in vine charcoal. Her dreadlocks were pretty complex, and give the brief amount of time, I had to simplify them more than I wanted to.
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| Step 2: Laying in shadows and halftones |
I mixed up a basic shadow hue (consisting of earth colors) for her skin, which is pale. The Palette and Chisel Academy, where the workshop took place, has excellent north skylights, so the light and temperature relationships were textbook: cool lights and warm, glowing shadows. So the shadow color, while dark, is warm. I also mixed and applied some halftone colors, which were more neutral, since technically halftones are cool, though this is somewhat contradicted by the warmth of the smaller facial features, where blood flows close to the skin surface, warming up the areas. I quickly placed the shadows and halftones on her hair.
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| Step 3: Adding lights |
Once most of the halftones were applied—I worked quickly using flat synthetic brushes and a flexible Japanese painting knife—I mixed and began placing the lights. Again I attempted to identify the warmth in the lights, which follow the rule that lights are warm, while highlights are cool. This proved to be the case, since the skylights admitted cool daylight, giving the highlights a bluish-white appearance.
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| Step 4: Completed oil sketch |
Here, with just a little time left, I focused on the individual features: I placed and refined the iris of the eye, the lights on the ear, and the details of the nose and mouth. I then briefly spent time on her neck and shoulders. The whole thing was a bit rushed, since I was also reviewing the students' work, but at least I got the features on the canvas at a reasonable level of finish.
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| Detail from flatbed scan |
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In this detail, a few things are visible: first, this alla prima sketch consists of a single layer, and in many places the imprimatura is visible between passages of thick paint. Second, the paint is applied with minimal brushing (or knife-blending), since in my view alla prima sketches look best with paint mixtures left as intact as possible. As a result, the transitional areas are not as smooth I as saw them, but the visual effects had to, for the sake of the medium, be subordinate to the properties of paint.
