Artwatch UK

Misreading Visual Evidence ~ No 1: David Hockney, an art historian and an x-ray photograph

26th March 2011

It was recently claimed that “fresh insight” gained on Caravaggio’s painting technique supports David Hockney’s theory that the artist used a primitive form of photography to create his paintings (“Exhibition sheds new light on the art of Caravaggio”, Daily Telegraph report, March 11th). Diagrams, mirrors and light boxes displayed in an exhibition at the Palazzo Venezia in Rome, were said to “show” that Caravaggio “may indeed have” used a camera obscura to project figures on to a canvas so that they might be painted directly, with “extraordinary realism” and without any need for designs or preliminary studies. Showing that someone may have done something cuts no ice when logic, logistics and the laws of art all combine to testify against the Hockney hypothesis.

“Insight” itself is a weasel term and is not the same thing as evidence. The art historian supporting Hockney’s thesis, Dr John Spike, offered the observation that “Gallileo was developing the telescope and they [artists] were all fascinated by optics” as if by way of some circumstantial corroboration. Whether or not they were so fascinated, we should note the absence of evidence and consider the logistical difficulties that they would have faced if attempting to work on the basis of the Hockney Hypothesis.

Are we really to suppose that all the figures and animals, and babies, and flying angels, writhing serpents, crucified men and beheaded victims depicted in Caravaggio’s paintings in arrested moments of extremis, were actually copied directly, literally, from life? More specifically, are we to suppose that various combinations of human, bestial and divine creatures were first assembled and then simultaneously posed in full costume for as long as it took the artist to convert their projected photographic image into his painted pictures? (See illustrations on the right.)

Or should we believe that each figure was individually copied down, in full costume, exactly as seen when projected through a pinhole onto a wall in a darkened room? If so, was each painted figure subsequently “overlapped” and partly obliterated by the next in the sequence? Is there any material evidence of such overlaps? If not, we would have to assume that Caravaggio painted directly onto only that part of the projected image that would remain visible when the next figure was copied in. Timing is an important separate consideration: whether the models were depicted in entire groups or individually, how long would they have been expected to hold their usually animated and dramatically expressive poses (see right) in a compositionally perfect position in relation to other figures not yet posed or painted?

There is another crucial consideration: were Caravaggio’s famously dramatic and theatrical lighting effects copied directly from nature onto the canvas via an image of a multi-figure tableau projected through a pinhole? Consider the exponentially increasing practical difficulties an artist would have to overcome when attempting to work in such fashion. Caravaggio would not only have had to paint at speed to avoid his models wearying and slipping out of pose, he would have had to have done so at a speed that would not allow the brilliant light source illuminating his figures to move – and to have done so when working not in front of his painting but to the side of the image projected upon it so as not to block it with his own shadow. Has any artist in history so handicapped his own labours?

Would the light source deployed on Caravaggio’s frozen models have been the sun? If so, at what time of the day did he work? At noon, with the sun’s all-bleaching brilliant light at its zenith, producing unhelpfully top-lit figures? Or in the mornings and evenings when low, acutely angled, less bright but faster moving and changing? Did Caravaggio not only anticipate photography, but Impressionism too? Or, would his groups have been lit for long periods by a fixed battery of brilliant theatrical lamps?

When it is claimed that Caravaggio had achieved the extraordinary realism of his paintings 200 years in advance of the invention of the camera, on the same logic it should further be claimed that he anticipated and emulated the achievements of the cinema. It took the full resources of modern cinema and means of lighting for Luis Bunuel to be able to compose and momentarily arrest a multi-figured tableau in mimicry of Leonardo’s The Last Supper in his film Viridiana. Is there any evidence that such human and technical resources were available to Caravaggio? Is it believed that Caravaggio had invariably worked in this manner? Or that he did so on some occasions but not others? Has any material evidence been found in Caravaggio’s paintings that reflects such radically different patterns of working methods?

The real problem with the Hockney thesis, however, is not the absence of supporting evidence but the existence of contra-evidence. The Telegraph report is illustrated by a photograph of Caravaggio’s The Calling of St Matthew, and by an x-ray photograph of the two figures at the picture’s right-hand side. Those photographs (see above right) constitute a material record of both the paint that is visible to the human eye and the hidden earlier underlying painting. The caption claims that “x-ray analysis shows the style of the artist and supports the idea that he used a primitive form of photography in his work”. It is hard to see how this might be so. X-rays are notoriously difficult images to read with confidence because while they show all the successive states of a painting simultaneously they do not pick up all pigments and materials equally.

Nonetheless, the x-ray photograph that is shown adjacent to the two figures helpfully permits direct visual comparisons. The most striking feature is that the underlying paintwork exposed in the x-ray is not identical with the paintwork that is visible to the human eye. Had Caravaggio worked in the manner being claimed, an x-ray would reveal no differences – no revisions, no “pentimenti”, nothing other than what was already visible on the picture’s surface. But the x-ray evidence here is doubly injurious. Firstly, it shows major changes to the pose of the figures – Christ’s raised arm is higher in the x-ray than in the painting while, conversely, his hand droops dramatically. Secondly, the image is sufficiently intelligible to establish major discrepancies of artistic style.

In the space of the figure (St Peter) standing in front of Christ, the type of drapery seen in the x-ray photograph is manifestly different from that now seen in the visible paint above it. One observer (Giorgio Bonsanti) attributed the underlying drapery, on the basis of an earlier x-ray, to the figure of Christ – see right. Certainly as drapery it is greatly more accomplished artistically – more “Raphael-esque” – than the comparatively stiff, angular, “bent-tin” draped material seen on the St Peter. Most damagingly of all, this underlying painted drapery is not just finer it is of a type found only in art and never in nature. It is not some literal mechanical transcription of an actual draped garment, but a conjuring of spirited flowing, wind-filled forms that arc around the body and derive from the laws of drapery that were first understood and devised by the God-like artists of antiquity and then later rediscovered and emulated by the greatest artists of the Italian Renaissance. The living sculpture drapery revealed by the x-ray could not have been taken down from a static figure because it was an invention, a product of art and imagination that served the great powers of composition, design and expression – it conferred grandeur, grace and dynamism to the theatrical stage-right entrance of Christ. We might reasonably agree with Giorgio Bonsanti (see right) that Caravaggio, having first created this great glory, then opted to suppress his own magnificence of drapery so as to have the secondary, Christ-obscuring figure of St Peter serve as a dull mundanely reproachful foil to the wealthily and vibrantly attired group of figures to his left. On the basis of this clear hard embodiment of artistically purposive thought and revision – to the point of artistic sacrifice – it can hardly be concluded other than that Caravaggio was a great inventive, self-critical self-revising showman of an artist and not some secretive shortcut-taking literalist.

Michael Daley

Comments may be left at:

Printer-friendly PDF version of this article

Above: the illustrations to the Daily Telegraph report “Exhibition sheds new light on the art of Caravaggio”, March 12th 2011.
Above: a comparative detail of Caravaggio’s The Calling of St Matthew, seen in the painting itself (left) and in the x-ray (right). Note Caravaggio’s radical revisions of anatomy and treatment of drapery that can be seen in the x-ray photograph on the right.
Above: a group of illustrations seen in Giorgio Bonsanti’s Caravaggio, London, 1984. In a passage that is highly pertinent to current discussions, Giorgio Bonsanti observed on the basis of an early x-ray of the figures of Christ and St Peter:

Caravaggio did not arrive at the final version right away, and it is important to remember that even compositions that appear to have been born in an instant are the fruit of a long preparatory study. X-ray analysis has proven absolutely indispensable in revealing to our later vision forms and figures that the artist, after sketching them on the canvas, believed would remain concealed from all eyes, including his own, beneath the final version. Thus, in an early version of the Calling of St Matthew, the figure of Christ stood alone and was not covered, as in the final version, by that of St Peter. The latter’s presence involved the accentuation, in the final version, of his role as mediator (he would be the first pope) between man and God. Indeed, we see a sort of division of Christ into two parts, as though two persons have germinated and branched off from the same trunk. This already emphasized Christ’s human and divine nature. Peter laboriously and almost stiffly repeats the gesture of Christ, which in comparison is handled with the greatest eloquence. In addition, we immediately notice the painting’s total independence from the designs of earlier religious painting. From this we may conclude that the artist is not interested in instructing, admonishing or stirring his audience to religious feeling, as the Counter reformation expected art to do. He felt it was not his task. He seems to say, this is what happened. Christ and Peter suddenly came in and made it clear that they wanted to talk to Matthew, while the two youths, taken by surprise, prepared to face an intrusion whose nature they were unaware of; and indeed two other figures, unaware of what was going on, continued counting the money. Matthew brought his hand to his chest, as though to ask if it were he that they wanted. An instant before, the scene had been different; an instant later, it would no longer be the same. If a scene is to be instructive, it must be prepared, planned, and arranged. If it is devoid of this kind of orientation towards a specific end, then the artist is virtually free to shape it as he likes and to change it from one moment to the next, not preparing it, but taking note of it.

Above; a detail from the Galleria Doria Pamphilj’s Caravaggio Rest during the Flight into Egypt. It would seem self evident that the figure of an angel is an item of artistic invention and not a rendering made on top of a photographically projected image of a posed model. In 1993 Eduard A. Safarik wrote of this arresting figure:

Caravaggio, who broke with tradition in his representation of this theme, was an unusual exegetist and his imagination produced revolutionary iconographic results. As protagonist of the scene, the painter inserts an angel seen from behind, placing the figure in a prominent position, in the golden section that splits the composition into two parts: the left-hand one, with St Joseph, the donkey, and stones, is dedicated to earthly life, while the right-hand area, which includes the Madonna and Child among living plants, is devoted to the divine world. Even the half-clad angel, for which ambiguous interpretations have forcedly been proposed, corresponds very precisely to the contemporary views put forward by Constantino Ghini in 1595 (the picture, painted at the same time as as the Mary Magdalen, dates from somewhere between 1595 and 1597) and Federico Borromeo, who held that the nudity of angels is a sign of their immunity from any contamination by human misery, just as the bare feet indicate that they are untouched by earthly things…The principal motif of Caravaggio’s Flight into Egypt is that of the music that can be heard on earth, considered by the Fathers of the church to be a copy of music in heaven. The intermediary between these two worlds is the invisible sound, which in art takes the form of an Angel playing music, a divine messenger that stands at the border between material and spirirtual reality. God communicates with men through Angels, who are his go-betweens:'[it is the] Angel who spoke to me,’ says Zachariah and for Ezekiel, the Angel is ‘man dressed in linen,’ just as Caravaggio depicts him.

Above: Caravaggio’s Deposition, the Vatican, Pinacoteca. A depicted ensemble of figures that could not be held for longer than seconds by any group of living models.
Click on the images above for larger versions. NOTE: zooming requires the Adobe Flash Plug-in.

Comments are closed.