Jennifer Letchet Paintings

My work explores fundamental elements of painting, the relationship between colour and line. I intend my paintings to affect the viewer optically with the illusion of shapes moving and receding. Colour theory is very important to my work. I use specific hues to symbolise ideas or emotions. The contained shapes on canvases seem more like objects than lines. My recent work explores natural and man-made disasters and the impact this has on our environment. I want to record the changing landscape through simplified shapes and colours.

Sunday, 13 November 2011

Gesso and Egg Tempera Painting

Gesso is an Italian word for white mineral gypsum and was used as a primer for wood or canvas.  It is a traditional mix of glue binder and chalk used as a primer for painting.  Its absorbency makes it work for water based paints: egg tempera and watercolours.  It is not suitable for oils as it is too porous a surface.

Gesso resembles paint in appearance, but is thinner and it dries hard. It is applied with a brush and must dry before the surface can be painted on. Gesso was first created for use in painting, to give the surface the right properties to receive paint. In Gothic and Renaissance panel painting, gesso was applied over a panel of wood to give the paint something to which is could adhere. It created a slightly rough surface and prevented the paint from seeping into the wood.  Gesso can be quite a brittle surface and if mixed wrong can crack.

Egg tempera is a permanent drying medium consisting of coloured pigments and egg yolk.  Egg tempera painting was the primary method until the development of oil paints in the 1500s. Tempera also refers to the paintings in this medium.  Tempera paintings are very long lasting and examples from the 1st centuries AD still exist, for example Egyptian sarcophagus painting and early panel painting by Michelangelo.

Egg tempera is traditionally created by mixing small amounts of pigment with egg yolk and distilled water.  The egg is separated to remove the white and then the egg yolk is pierced to remove the outer membrane.  The mixing and amounts cannot be measured, but must be judged by eye.  The consistency should lie somewhere between watery and greasy.  Some pigments are unstable and therefore require more binder, i.e. yolk.  Depending on how thick you wanted your tempera to be, you would add more or less water.  Despite being a water-based paint, it is not water resistant and therefore the paint will not keep more than a few hours.

If you wanted a quality of paint more akin to oil paint, you would mix a ratio of 1:1 of yolk and linseed oil to your pigment.

Tempera paint dries very quickly and is best applied thinly in semi-opaque layers.  You will build up the colour in layers and it allows for experimentation with different coloured layers.  The finished appearance is matte and smooth.  The advantage over oils is that oil colours will yellow in time, but egg tempera colours do not alter over time.

Tempera adheres best to an absorbent ground with a lower oil quantity than itself, which is why oils are not suitable.  Tempera and gesso requires a hard surface like board, and not a flexible one like canvas as it would crack otherwise.

Tempera painting became out of favour in the Late Renaissance but it was rediscovered by artists such as William Blake, and the Pre-Raphaelites.


Anonymous said...


Jenee Galante said...

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Roslyn M. Spence said...

painting is a difficult technique, it requires more experience. thank your article. :)

Anthony said...

Although painting my own beads can take a lot of precision, it will also be a lot of fun, and once I know what I am doing, I will find that i can put tons of new ideas into practice. Thank you!

Joshua said...

really nice writing, great article, thanks for sharing!