Process and Drawing
The form of the altarpiece
The size and shape of the painting would likely have been stipulated in the commission. The stone altar and frame for the painting would have either been present in the church already or, ordered and built separately.
Assembly of the panels of the canvas
The support of the Petrobelli Altarpiece is a twill linen canvas. Bolts of canvas were usually not much more than a metre wide – the normal width of a loom. For larger paintings this would involve piecing together several lengths of fabric. The support for the painting was made of three lengths of the twill canvas sewn vertically. This canvas would have then been stretched onto a wooden framework. The stitching was then covered with a lead-based oil putty to mask the visible stitching and any puckering it had produced.
Application of the layer of gesso
Once the fabric support was ready for painting, it would likely have been coated with a layer of animal-hide glue to “size” it, and then covered with gesso. This preparation, typical of Veronese’s practice, was also used in The Repentant Magdalen and The Rest on the Flight into Egypt.
Marking out the design and central plumb-line
The first mark made on the surface of the gesso was a vertical line that ran straight down the middle of the canvas from top to bottom. The line was drawn in charcoal while the gesso was still soft. Its primary function was as a reference from which to plot out the symmetrical architecture.
Insertion of architecture
The architecture was then drawn in, creating a space where the figures could be placed. The architecture is of the ionic order, and the structure is similar to others designed by Andrea Palladio (1508 - 1580), a contemporary and friend of Veronese. Palladio is one of the most influential architects in the history of western art. We do not know what the architecture of the Petrobelli chapel looked like, but Veronese often designed his painted architecture to work with the real architecture around it.
Insertion of reference lines for the figures of Christ, the patrons and the saints.
Vertical lines and one central horizontal line were then drawn in the places where Christ, the saints and the patrons were planned. These lines facilitated the transfer of preparatory drawings for the key figures – much in the same way squaring up is traditionally employed – likely corresponding lines were laid over the preparatory drawings. Full squaring up was perhaps considered unnecessary, or the horizontal lines were perhaps threads strung across the width of the canvas that were removed once the drawings were transferred. Another factor here was possibly that the vertical elements of a grid were avoided to allow the in situ adaptation of the drawings to cope with the fact that the altarpiece would have been high and viewed from below, and the figures are a little stretched to accommodate this. The lines also seemed to have served for the accurate scaling of figures. The reference lines for the lower tier of figures are roughly twice as far apart as those for Christ, which is correct for the depicted space.
Drawing of Christ
The first figure drawn of the group in the upper part of the painting is that of Christ, drawn carefully in charcoal and likely from a preparatory study made from life. The central axis of the painting passes directly between his eyes and the reference lines here were built around this central plumbline. Christ’s upper body and arms are elongated in relation to his foreshortened legs – a distortion that works when viewed from below.
Drawing of the patrons and auxiliary saints
The figures of the saints, patrons and Satan were transferred to the canvas with the help of the reference lines and therefore probably from relatively detailed preparatory drawings. Christ seems to have been transferred from a figure study to ensure accurate depiction of anatomy, and was not changed during the painting stage. The figures on the lower tier however need not have been drawn from life, and were adjusted as the painting progressed. We do not know whether the portraits of the donors were painted from life, but it would seem likely that portrait drawings were made, and would have been used at this stage.
Drawing of angels supporting Christ, and adjustments to other figures
The angels supporting Christ were drawn on the canvas in a bold freehand with black oil paint, and may have not had detailed preparatory studies. For instance the legs of the Angel on Christ’s left are drawn along with swags of drapery to cover them. Veronese may have been working directly from loose initial drawings – the primo pensieri.
It was at this stage that Veronese also made adjustments to the figures below, in the same black paint. The most prominent modification explains a strange form seen just behind Saint Anthony in the Edinburgh fragment. Veronese seems to have experimented with a more upright figure for the Saint, with his crozier over his left shoulder. This was perhaps to avoid the obvious formal symmetry of the two Saints, each leaning over his respective donor, and perhaps also to move Saint Anthony’s head away from the join in the canvas. He ultimately followed the form of the initial drawing, but did not decide on which head to use until the roughing in of the paint was underway, which is one of the reasons this phantom head is so visible today.
Insertion of putti, and other details
The swooping putti have drawing unlike the other figures and forms on the canvas. They have no internal features and their outline is subtle and linear. This may be due to the use of a cartoon, or simply direct drawing from fairly large preparatory drawings. The winged heads in the centre of the painting have no drawing, and were put in directly in paint near the end of the painting process.