The Iridescent Umber| Νο7/79
Fe2O3 (H2O) + MnO2·(n H2O)+ Al2O3 + [Xe] 4f14 5d10 6s1
The colour Structure
For a mural, the wall is an integral part of the artwork. The colour stratification creates chemical reactions with the wall, resulting in the quality of the paint with unique textures in terms of hue, saturation, brightness, contrast, and density.
In the past, during a fresco work, the colour and the wet plaster were molded together, creating the color textures that the frescoes of the Byzantine monumental painting have. Mural on dry lime (secco) presents different behaviour, but, again, the wall plays an important role in colour quality.
Iannis Karoussos used the wall as his most important medium, rather than a simple painting surface. He worked with colour layering, to make the most of the wall. Colour layering is created by adding thin layers of colour, leaving the wall to create the colour qualities.
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To transfer the layering technique to the digital environment, so that the mural work can be transferred accurately, the photographic capture is insufficient and often distorts the work itself, as its technology - either analog or digital - has default conditions, such as the focal length, depth, and perspective that contrast with the characteristics of Byzantine art. After many different tests on Karoussos's artwork in several churches, the on-site scanning procedure was deemed the most appropriate. The flat scan, directly on the wall, transfers, evenly, the entire structure of both the color layers and their quality on the wall.
This process, applied by the Karoussos Archives for the transfer of the mural set to the digital environment, allows the transfer of the layering technique, without the distortions of the photographic lens. With this technique, fragments of Karoussos colour layering were transferred to the digital environment, to select the predominant colour range for the colour structure of St. Spyridon chapel. Based on the artist's palette, umber, ochre, and sienna were chosen, emerging the golden umber of St. Spyridon chapel. With the technique of flat scanning, colour sets were transferred from Karoussos's murals to the digital environment, to select the dominant series for the color structure of St. Spyridon chapel. Based on his color palette, umber, ocher, and sienna were selected, emerging the chapel's colour structure.
The acclaimed technique of the artist's plain painting was painted in situ, on the walls of the chapel. Then, another flat scan on the chapel's wall was applied, so the emerged colour to be integrated with the hybrid frescoes, to create a unified aesthetic result, through the cohesion of the artwork and the walls.
flat scanning
The Formula
Umber
Umber is a natural blend of iron and manganese oxides and hydroxides. It is used throughout the cultural history of mankind, has earth tones that are graded according to the amount of iron and manganese compounds and is stable. It is therefore a natural mineral that consists of silicon and clay that owes its color to iron oxides. It is mined and washed, leaving a mixture of minerals - essentially rust - in the form of colored clay.
These brown earth pigments are now also known as Sienna earth, but the umber is darker than similar Sienna earth pigments and brown ocher.
The name umber comes from terra d’ombra, land of Umbria, a mountainous region of central Italy from where this dye was mined. The name may also be related to the Latin word umbra which means shadow. It is one of the first pigments used by man and is found along with carbon black, red and yellow ocher in the cave paintings of the Neolithic period. Umber has been extensively used in the frescoes of Byzantine and post-Byzantine period. However, it was not widely used in Europe, until the end of the 15th century. The Renaissance painter Giorgio Vasari mentions it, as rather a new color for his time. It was a key color in Caravaggio and Rembrandt palettes for the Chiaroscuro technique.
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Gold
Gold in the universe is traditionally thought to have originated from nuclei in supernovae, which feed the dust disks that form the various stellar systems. Because the Earth had melted during its formation, it is believed that almost all of the original gold it contained, sank to its core. And the gold that is, nowadays, in its crust and in its mantle, is considered to have fallen later from the initial formation of our planet, during its gradual subsequent heavy bombardment by asteroids and comets, for about 4 billion years.
Chemically pure gold, under normal ambient conditions, is a dense, soft, glittering, slightly reddish yellow solid metal. Gold and copper are the only two "coloured metals".
Its color is determined by the frequency of plasma oscillations among the metal's valence electrons, in the ultraviolet range for most metals but in the visible range for gold due to relativistic effects affecting the orbitals around gold atoms.
Reflecting the Platonic World of Ideas, Byzantine painting seeks, with the light of color, to reveal the intangible substance. The light, which is identified with God, catalyzing the materiality of being, unites everything into an integrated sum. This is exactly the unity that the golden background of Byzantine works gives, yielding a transcendental dimension to the space. After all, the symbolism of gold connects it with the meanings of the precious, the incorruptible and unchangeable, the divine.
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The Iridescent Umber| Νο7/79
The color that illuminates the chapel is described as a spiritual and transcendent glow with a warm shade of umber, imbued with atoms of gold.
Its texture is velvety and when visitors change their position in the space, the visual performance of the color changes accordingly, as if one is changing the direction of the pile of a velvet fabric.
The composition of 7/79 comes from chemical reactions of each one of the pigments independently, but also between them. The color produced by the intersection of physical and digital processes, is also capable, in addition to the above, in environmental interactions. Specifically, it interacts in the space that is applied, both in relation to the surrounding elements, and in the visual perception of its viewer. This means that the properties of 7/79 are different from the type of its original pigments.
In Paleolithic painting, people developed the technique of heating substances to produce a new substance. A chemical reaction in which yellow ocher produces a new red substance different from natural hematite or red earth (terra rossa). Similarly, iridescent umber is a new substance, produced by the development of the technique of hybridization of its components, a reaction in which the interaction of the elements of natural umber and gold, produces a new substance, capable of enhancing the visual experience.
The transcendental golden light as it blends with the riveting shadow of the umber tones, leads the gaze beyond its natural dimension, thus contributing to the liturgical purpose of the space.
