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| Techniques |
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| Tempera On Wood |
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| Works |
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:: Madonna and Child between Sts. Anthony Abbot and Lucy |
| Florentine Painter,
First quarter of the 16th century |
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:: Madonna and Child between Sts. Bartholomew and Francis |
| Francesco Granacci,
Last decade of the 15th century |
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:: Madonna and Child enthroned between St. John the Baptist and St. James della Marca |
| Master of Signa,
First half of the 15th century |
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:: The Archangel St. Michael and stories from the legend of his life |
| Coppo di Marcovaldo,
1250-1260 ca. |
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:: St. Anthony Abbot, St. Sebastian and St. Rocchus |
| Master of Tavarnelle,
1510-1515 ca. |
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:: Madonna and Child enthroned between Sts. Sebastian and Martin |
| Master of Tavarnelle,
1510-1515 ca. |
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:: Madonna and Child |
| Meliore,
1270-1280 ca. |
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:: Madonna and Child between the angels Raphael and Gabriel |
| Master of Marradi,
1470-1480 ca |
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:: Madonna and Child |
| Lippo di Benivieni,
Second decade of the 14th century |
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:: Madonna and Child |
| Ambrogio Lorenzetti,
Dated 1319 |
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:: Annunciation |
| Florentine Painter,
Mid 14th century |
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:: Lamentation over the dead Christ |
| Neri di Bicci,
Mentioned in documents in 1473 |
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:: Coronation of the Virgin |
| Neri di Bicci,
Dated 1476 and 1481 |
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Tempera - or "tempra" as we once said in ancient Italian - is the
technique of painting whereby the colour is dissolved in water and that
can be held together by various substances, with the exclusion of oil:
emulsions of egg, milk, fig lattice, glues, gums, waxes. It was the
principal method of painting, almost all of which was carried out on
wood, before the introduction of oil painting that took place between
the 15th and 16th centuries.The treatise on art written by Cennino
Cennini in the late 14th century describing the methods used in the
workshop of his teacher Agnolo Gaddi is an indispensable source for
discovering the methods used for painting on wood from the 13th and
throughout most of the 14th century, though it was also a very useful
point of reference for later artists.
The wooden backing
Poplar wood was generally used for the backing of tempera paintings
in Italy. The panel was made of several pieces of wood glued together
and reinforced on the back with shaped crosspieces that were fitted
inside a groove chiselled out of the thickness of the wood. The backing
was usually strengthened with an outer frame (though it also had an
aesthetic function), fixed with nails that were hammered in from the
front and then bent in at the back.
Preparatory layers
Once the wooden backing had been completed, several coats of animal
glue, a substance that soaked into the wood and helped the next layers
to adhere, were applied to the surface of the panel. Some strips of
linen cloth soaked in glue were then applied to the finished surface
and scraped well to obtain a uniform surface. This was followed by
alternate layers of gypsum (sometimes as many as eight), held together
by a thin film of glue between one coat and the next: the first was the
thickest, formed of quite a large grained material, while the rest,
carried out with very fine plaster, got gradually thinner and thinner,
until the surface lost most of its porous and absorbent capacity. This
elaborate preparation also helped to mitigate the movements of the
wooden backing, thus safeguarding the integrity of the painting.
Gilding
Gilded backgrounds were formally abandoned at the beginning of
theRenaissance, but more conservative artists continued to use it for
the whole of the 14th century. The background gilding was spread over
the panel before starting to paint it in tempera. Several coats of
bole, a clay that can be found in nature in various colours, mixed with
egg white or animal glues, were spread on the areas where the gilding
was to go. It had a double function as it made the panel surface
highly adhesive and gave the gilding varying levels of transparency.
Once the gold leaf was applied on the layer of bole, dampened with
water, the surface was polished with a burnisher (an instrument fitted
with a hard bone or, often, an agate point).The haloes were drawn with
a compass on top of the gold leaf and afterwards decorated with
punching.
Silver gilding varnishing
Silver rather than gold leaf was often used, basically for economic
reasons. The surface was then covered with a special yellow coloured
varnish, called mecca or silver gilding varnish, which gave the silver
leaf the aspect of the more precious gold leaf. Silver guilding varnish
was made by mixing together a series of vegetable resins in various
colours and shades: sandarac, gambode, dragon's blood and aloe.
The drawing
At this point the drawing was carried out, traced directly onto the
wooden panel or taken from a cartoon. If a cartoon was used, the
drawing was transferred to the panel using the pouncing technique, in
other words, a sharp point was used to make holes all around the
figures on the sheet of paper, which was then placed on top of the
wooden plaster-covered surface. With the aid of a canvas pad, a layer
of carbon dust was passed along the lines full of holes. The tracing of
the drawing remained when the cartoon was removed from the panel, and
then retraced with a small brush soaked in ink. The general layout of
the composition was then fixed by cutting into the outlines along the
outer profile of the figures and also where the details and areas of
shadow needed to be defined. These cuts could still be seen after the
first layers of colour and could therefore act as reference points for
successive stages in the painting.
Colours
The colours were obtained by the grinding up of earths, resins,
stones or other natural materials, and afterwards diluted and mixed
with various kinds of emulsifying agents. The most commonly used were
the following:
BLACK
vine black (vegetable, burnt vine shoots)stone black (vegetable, burnt almond stones)smoke black, coal black
RED
vermillion (natural mineral)dragon's blood (resin taken from palm leaves)
YELLOWyellow ochre (clay)lead and tin yellow"risalgallo" (composed of
arsenic)orpiment or arsenic trisulphide (composed of arsenic)
GREEN
green earth (natural mineral)verdigrismalachite green
WHITE
ceruse or lead white (artificial mineral)white of San Giovanni (from purified slaked lime)bone white (from oxidised bone)
BLUE
azurite (mineral)ultramarine or lapis lazuli blue (natural mineral)indigo blue (vegetable)
The preparation of tempera
There are numerous recipes for preparing tempera, which vary according to the type of emulsifying agent used.
Tempera with glue: is prepared by mixing the
pigments with animal or vegetable glues. This type of tempera boasts a
very positive quality in that it is particularly luminous, but the
mixture tends to be somewhat fragile and leave marks as it dries.
Tempera with wax: is a mixed method that is part encaustic and
part tempera painting, in use since the Middle Ages. This type of
tempera used lime as an alkalescent to be able to mix the wax with
water; ammonia has been used to have the same effect in modern times.
This type of painting is also extremely resistant against damp.
Tempera with egg: this is the tempera of the 15th century
Italian painters, whose recipe has been passed down in the Cennini
treatise. The author-artist indicates two methods for making tempera:
the first consists in beating up egg yolk with chopped fig twigs,
because the liquid that comes out of the twigs when mixed with the egg
tends to delay the colours from drying on the palette and thus makes it
easier to apply; the second consists in mixing only the yolk of egg
with the colour, which gives a good tempera for painting on all types
of surface.
Spreading the colour
Methods of utilising tempera have varied in time according to
changes in styles and artistic culture. Three great periods in
particular denote the evolution of the way colour was spread:
a) The first period covered almost the whole of the 13th century,
prior to the 14th century innovations. Colour was spread on the 13th
century paintings on wood in uniform coats and superimposed lines. This
procedure required a series of operations that included the preparation
of colour followed by spreading several layers of these colours on the
surface of the painting. Once the drawing was completed, the
painter spread the colour evenly, gradually adding new earths, before
starting to carry out the details of the faces (eyes, mouth, wrinkles,
beard...) and the areas of light and shade. This was basically a
graphic system where the image was treated like a two-dimensional
painting. The graffito technique was often used to decorate some of the
details (such as drapery, cushions, borders), so as to create a
contrast between the shining metal and the brilliant colours of the
tempera. A coat of colour was applied on top of the gold or silver leaf
and then scraped off with a stylus, so that the metallic surface could
shine though.
The skin colours were painted last of all, first with a
base coat of "verdaccio" (a mixture of ceruse, yellow ochre and black)
that gave transparency to the surface and thus emphasised the light and
shade. The basic colour was a mixture of vermillion and ceruse which
was spread with tiny brush strokes so as to create a changing
chiaroscuro that brought out the various shades.
b) The surface was no longer covered with even coats of colour with the new methods introduced between the 13th and 14th centuries. The various shades of colour were instead spread to combine and blend in together.
Previously prepared colours were used, area by area, until the painting
was completed instead of applying first one single colour and then
another to the surface. In this period the first coat to be applied was
a gold leaf background (see relative notes), before starting to paint
the colour. This method is described in detail in Cennino Cennini's
Book on art.
c) Colour continued to be used as described by Cennini for the whole of the 14th and the first half of the 15th centuries.
Veiling, a new technique developed in the second half of the 15th
century, covered the drawing with a transparent layer that modified the
colour beneath and thus obtained a wide variety of chromatic shades and
luminous reflections. This technique made it possible to give paintings
the spatial depth that was the conquest of the Renaissance painters.
Varnishing
When all the colours were completely dry, a coat of transparent and
colourless varnish was spread over the panel. This was generally
limited to the painted parts alone, but in some examples this patina
also covers the gilded background. This final operation protected the
painted surface from external damage and ensured the lasting brilliance
of the colours in time.
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