Picasso’s Guernica (Gigapixel Analysis)

The evolution of Picasso's painting was documented by the photographs that Dora Maar took while the artist was painting the picture. In these series, the changes in composition that the artist worked on in successive stages are clearly appreciated.

Currently, these changes are made visible in Guernica thanks to studies with infrared reflectography, as they allow passing through the successive layers of paint.

Bull's head: Infrared reflectography analysis reveals eyes in the bull's head that remain hidden by the white color layer.

Alterations of the support The canvas has suffered serious alterations derived from the multiple nailing and unnailing to which its frame was subjected during its numerous transfers.

In some cases, differences can be established between craquelure and fissures. Although fissures are more numerous, craquelure is more serious, longer, and, in many cases, affects several layers: the protective layer, the pictorial layer, and the preparation layer. It should be noted that the presence of craquelure or fissures is directly related to the thickness of the polychromy. If it is thinner, fissures usually appear, and if there are more impasto areas, strong craquelure is detected.

On February 28, 1974, Guernica suffered an attack with red acrylic spray paint. The attack was carried out by one of the members of the Art Workers’ Coalition group, Tony Shafrazi, who wrote on the canvas "Kill lies all". The varnish that had been applied in 1962 served as a protective layer for the polychromy, and the red paint could be removed without the original suffering damage.

Currently, macro photographs show a series of reddish micro-residues practically imperceptible to the naked eye, and, in some cases, introduced into the fissures.

Technical Glossary:

• Adhesive paste: Obtained by mixing waxes and natural resins in variable proportions.
• Craquelure: Cracking of the paint and preparation in various forms (spider web, network, etc.) that can cause cupping and detachment of the pictorial layer.
• Fraying (Desfibrado): Small fragments of the warp or weft that separate from the fabric support.
• Crack (Grieta): Linear cracking that occurs in the pictorial layer, preparation, or support.
• Stain (Mancha): Residue of a different nature on the pictorial surface.
• Micro-craquelure: Superficial indentation that occurs in the pictorial layer.