Painting / under painting

Painting.

During these session we explored a range of different painting mediums and processes.

We have used:

• Gouache - a water-based painting medium that is ideal for flat, strong colours (graphic designers use this as a preference because of this)
• Acrylic - Another water based painting medium that is slightly less viscous than Gouache and is ideal for larger paintings.  
• Oil - an oil based painting medium.  This can be thinned with turps (turpentine or white spirit*) or linseed oil.     Using linseed oil maintains the paint colour better than turps as this can dilute the colour.  Oil paint cannot be mixed with water, as the oil and water will separate. 

 *these are highly flammable and corrosive so contact with skin and eyes should be avoided (although a small amount on hands won't do any harm - unless you have sensitive skin (such as eczema)

 Equipment.

Brushes - We have used two different types of brushes.

Sable.

Sable brushes have soft bristles and are commonly used for watercolour, Gouache and Acrylic painting.  They hold water well, which makes them great for creating washes of colour as well as for more detailed work.




Hog-hair.

Hog hair brushes have tougher bristles and are ideal for acrylic and oil painting








Under painting.

http://artopiamagazine.com/wp-content/uploads/2014/02/16-9484.jpg

An underpainting is an initial painting that artists produce to establish tonal values of the subject prior to applying colour.  This usually begins with a general wash of Yellow Ochre mixed with a little Burnt Umber thinned down with Turpentine (white spirit) as a ground (the surface on which the paint is applied).  It is important that the paint does not create any kind of texture when applied, as this initial painting will disappear once colour is applied.  A combination of Burnt Umber and Yellow Ochre is then used to identify to tonal values of the piece.

This under painting is an extremely useful process by which the painter can analyse tonal contrast, shape and form, before concerning themselves with colour mixing and application.  Colour can then be gradually built up on top of this.

We looked at fabric, using oil paint, to create a ground and then an initial underpainting.  As the fabric was white, it was important to also consider the contrast between this and the darker background.  The dark tones in the background (as seen below) has created a stronger sense of depth and enabled the artists to emphasise the lighter, subtle tonal variations within the white fabric.