Tuesday, September 20, 2016

How an Artist Creates the Illusion of Depth with Paint Alone

In good sacred art, even the look of the negative space around the figures is carefully controlled by the artist.

The iconographic tradition portrays the heavenly realm, which is outside time, and crucially in this context, outside space. In order to convey a sense of the heavenly order in an earthly image, all sense of depth beyond the plane of the painting is deliberately eliminated. There is no superfluous background in an icon, and the negative space around a figure is meant to appear flat.

This first icon was painted in the 20th century by Gregory Kroug, a Russian ex-patriot living in Paris.

The naturalistic tradition, in contrast, seeks to do precisely the opposite, as we see here in a 15th century painting by the Venetian Giovanni Bellini.

It is portraying Historical man, that is man after the Fall, but not yet redeemed; this is the world of time and space that we live in. When painting in this tradition, the artist deliberately sets out, therefore, to create the illusion of space, which he can do in a number of ways. One is to draw a scene with conventional perspective (and the icon painter can do the converse by using inverse perspective). However, in order to use either form of perspective, there must be a background scene painted in the area around the main figures onto which the artist would apply them. If there is no background scene, the artist must use other means to control our sense of how the negative space appears, either as a three-dimensional space or as a flat surround in the plane of the painting.

This is done by the choice of medium or media used in the painting; one option is to gild, which always looks flat, as you can see this 12th century Greek icon of Moses at the burning bush.

If the background is painted rather than gilded, then egg tempera, fresco and mosaic always tend to look flat too, whereas oil paint, especially when used for painting shadow, always creates a strong sense of space beyond the plane of the painting.

Just to illustrate, compare the icon above by Gregory Kroug with another work by Bellini, his Sacred Conversation painted in 1490. Neither has scenery around the figures, yet first has a white background that is designed to eliminate as far as possible any sense of space beyond the plane of the painting. Bellini, on the other hand, has painted a dark background that plunges into the depths, and gives a sense of almost infinite space – there is a gaping chasm beyond the figures.

The next painting, done just 4 years before Bellini’s by Carlo Crivelli in 1486, demonstrates why the standard choice of medium became oil rather than egg tempera. In this image of the Annunciation, Crivelli uses single point perspective to create a sense that the pathway on the left is receding far into the distance. The draughtsmanship is fine, but for me the painting just doesn’t work. I have seen the original many times in the National Gallery in London, and every time I am struck by the fact that although the size of the figures in the background and all the perspective lines pointing to them tell me that they are in the distance, they simply don’t look distant, they look small. The reason, I feel, is the medium that Crivelli is using is egg tempera.

Even beyond the choice of medium, there are also ways of manipulating the paint so that it can enhance or reduce the natural look of the paint in this respect. These are called “glazes” and “scumbles.” I do not know for certain, but as far as one can tell from the reproductions, my guess is that this is what Kroug and Bellini were using. Certainly, if I was trying to create the same effect, this is what I would do.
Glazes and scumbles are created when a translucent layer of paint is put over another layer. When the tone of the upper layer is darker than that of the lower, it is called a glaze; when the tone of the upper layer is lighter, it is called a scumble. If I were seeking to create the Bellini effect, I would use a glaze in the background; and if seeking to create the Kroug effect, I would use a scumble.

When light hits the surface of the painting, some light is transmitted through to the lower layer of paint, and some is absorbed and reflected back. This reflected light bears the character of the layer that absorbed it. This is why, for example, when you shine blue light on paint, that it appears blue. Consider now the light that was not absorbed, but which passed through the layer of paint, and falls on the layer of paint underneath. At this interface the same thing happens again: some is transmitted and some absorbed and reflected. This goes on right until some of the light penetrates all the way through to the ground. If the ground of the painting is white and very reflective, a good part of the incidental light comes back out of the painting.

When we look at a painting, what the eye sees is the aggregate of different rays of light emerging from differing points within the paint layer and bearing the mark of the layer that last absorbed and reflected it. When I paint with tempera, which can be diluted into thin washes of paint, the final effect is the cumulative result of as many as 15 layers of paint of varying tones and colours. If you shine a light directly onto the painting, then the optical effect is that the painting is itself a source of light. It is especially beautiful if the light is a flickering candle. If you use a glaze with tempera, the usual medium for icons, it creates richer, jewel like surface. If you apply one in oil, the effect is even more dramatic, as it causes the surface to appear to sink into the deep distance. The shadows of baroque art, such as we see in a Rembrandt, seem to sink into the infinite. This effect is created by a glazes and it is perfect for the numinous, mysterious feel that baroque artists sought, as here in Rembrandt’s St Bartholomew.

A scumble, on the other hand, creates the opposite effect. The upper layer appears to float on the surface. As a general rule, it is less useful to an artists, and so you don’t hear them use the term very often. However, it is extremely useful to any icon painters wishing to create this Kroug effect. You simply ensure that the final layer of paint is the lightest in tone. If the layers underneath are a combination of glazes and scumbles, it still looks interesting and varied, but thrust forward, rather than sinking back into the painting. What I find so lovely about Kroug’s works is the huge variety of washes of tone and colour that he applies underneath the upper layer, be it glaze or scumble.

So many modern attempts at icon painting don’t do this; the colours are flat, dull and lifeless because they are created by the painting of a number of thick layers of the same paint, like a do-it-yourself decorator painting a wall.

The painting below is The Virgin at Prayer by the Italian artist Sassoferrato, a baroque artist who uses oil to create sinking depths in the negative space around the Virgin. What a wonderful painting! This is in the National Gallery too, and I make a point of going to look at it every time I visit the gallery.

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