Tuesday, June 17, 2008

Mixed media: Pastel and Acrylic Medium on gessoed canvas.

This demonstration is dedicated to all of my students who continue to enrich my teaching and artistic practice.

Thank You All.

Pastel artists are forever looking for the ideal surface upon which they can lay their colours. Gessoed canvas, usually used for oil and acrylic painting is a great surface to work on with pastels. The rough surface has the tooth needed to hold the pastel pigment and it can be tinted to any colour. I will go one step beyond tinting the surface, I will create a tonal under painting using dry pastels and painting medium. Painting medium is the ideal fixative, the under painting colour adheres permanently to the surface giving me the freedom to go create a lovely complex colour structure.

Pastel is essentially pure pigment which has been binded together into a solid stick of colour. When it is dampened with water, acrylic medium or oil medium it will behave much like paint. A gessoed canvas, cut to desired dimensions, can be used as a support for pastel paintings in which acrylic or oil based mediums are used to create a mixed media painting. Once a layer of pastel is put on the canvas, a brush dipped in painting medium can be brushed over the surface. When the surface is dry, an under painting is created, upon which dry pastels can be used to create a pastel painting. One can choose to use a fast drying alkyd based painting medium such as Liquin or an acrylic painting medium. I prefer acrylic medium because it will dry quickly affording me the immediate quality of working with pastels. Alternatively one can use watercolour paper and water to create a water colour under painting upon which pastel can then be added.

Preparation for under painting - Portrait.

This initial stage is important in order create a structural foundation for the subsequent drawing. For a portrait, proportion and tonal structure are essential. I will start by place the proportion lines of the face- getting the angles moving in the right directions. I will work from the central facial features, moving outward. The contours of the face and the hair will come last.

When sketching the initial features of the face, I will use both line and tone, searching for the dominant lights and darks which will give the face some dimension. I will not pay allot of attention to details at this point. They will be focused on in the later stages of the pastel drawing.

The choice of colours is of course a personal creative choice. For portraits, I will often use a dominant cool colour for the under painting, upon which I will then build up the warmer skin tones. I will use only one tone and one colour of pastel at this point. Remember an under painting is a structural base and not a finished product.

It is important that the whole surface has been covered with colour, (not just the central subject).

Under painting in Acrylic

After having blocked in the major masses of light and dark, using a brush and acrylic medium, I will lightly brush over them. I will start with a round brush, outlining some of the central features. A larger flat brush is used for the rest of the surface.

The pastel will become like paint at this point.
The density of the pastel on the
surface will determine how opaque or transparent the pigment will become when mixing it with acrylic medium. The tones will become darker when they are dampened with the medium. The light/dark relationship created in the initial drawing is respected and the surface is not overworked with the brush.


Painting medium and brushes are now put aside and the surface is worked with dry pastel only from this point on.

In pastel, I prefer to work from dark to light, progressively building up the lights. I will start by building up the middle tones and then the light middle tones. I am focusing on the overall facial structure, large shapes and colours notes created. The details of the facial features are still simplified at this point. I am working mostly in warm colours at this point, in order to build up skin tone colours.

I will slowly build up the light, medium and dark tones to create dimension and structure. Details will be cautiously added towards the
end of the work.

The surface is worked on equally. I try not to sacrifice any
one area in order to finish another.

Having laid out the basic colour scheme, I will start to work on the more subtle aspects of the composition. At this point I am softening the transitions from light to dark. This is done by working light over dark to create a smooth gradation of tone and colour.

More attention is paid to the eyes, mouth and nose,
refining their shape and colours. I also reintroduce
cool colours in the shadows. The cool colours are in
violets and blue violets, much like the under painting.

In the final stages of the pastel, the lightest lights are added, and the last subtle details to the whole work are added

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