A Guide to Art Analysis Techniques: From Paint to Printmaking
Stratigraphic Paint Analysis and Restoration
This section discusses the different layers of a painting, analyzed with a microscope. From preparation to varnishes, each layer reveals insights into the artwork’s creation.
Macrophotography
This technique reveals almost invisible details, such as the characteristics of brushstrokes and crackle patterns (the breakdown of the pigment-binder mixture).
Raking Light Photography
This method helps identify the pace and direction of brushstrokes, surface irregularities, and areas of swelling.
Ultraviolet (UVA) Light Analysis
UVA light reveals the fluorescence of materials. The rays are absorbed in inverse proportion to the compactness and age of the materials, highlighting opaque areas, alterations, and recent additions.
Infrared Analysis
This technique uses photographic film sensitive to infrared radiation. It provides information on red areas, while green, brown, and blue appear dark. Infrared analysis can reveal underlying images and detect overpainting.
X-ray Analysis
Useful when the artwork’s support doesn’t obstruct X-rays, this technique can uncover additions, repainting, preparation techniques, modifications, and regrets. It’s valuable for reference and detecting forgeries.
Mosaic Art
Originating from stone pavement (litóstrato) in Crete, mosaic art evolved to incorporate tiles in the Hellenistic period.
Opus Sectile (Intarsia)
This technique uses irregularly shaped, cut marble slabs to create designs with large stones.
Opus Tessellatum
This method employs regular, cubic tiles to form the mosaic.
Opus Vermiculatum
This technique utilizes smaller tiles in varied arrangements for intricate designs.
Trencadís
Emerging in the Contemporary Age, Trencadís uses ceramic fragments combined with mortar.
Printmaking Techniques
Printmaking involves creating identical reproductions using molds. The artist prepares a cast on a support, and the printer makes copies.
Woodcut
Woodcuts should be free of cracks. Tools like chisels and punches carve the wood surface to create the desired pattern in high relief. Ink is applied with a roller (only to the raised areas), resulting in distinct lines. This method is limited in the number of prints it can produce. Gauguin and German Expressionism revived woodcut, drawing inspiration from medieval primitivism.
Intaglio
This metal-based technique emerged in the 15th century, using sheet metal (hence the term “metal replica”). Copper, iron, or zinc are common materials. Intaglio allows for intermediate shades and greater depth than woodcut. Copper, though hard, is malleable and relatively inexpensive. Tools include chisels, punches, varnishes, waxes, resins (for surface preservation), ink, and a printing press. The design is engraved onto the metal, inked, and then printed.
Types of Intaglio
- Linear: The artist uses a tool that directly marks the copper, leaving a distinct line without nuances. Examples include engraving (using a triangular-sectioned tool) and drypoint (using a conical-pointed tool).
- Pictorial Effects: Developed in 17th-18th century Germany, this technique achieves shades and contrasts. A serrated grating, silicon disk, or steel comb creates grooves on the plate, resulting in textured, granular ink application.
Acid Etching (Indirect Intaglio)
The artist works on a prepared layer on the copper surface, scratching the design with a pointed instrument. Nitric acid (etching) bites into the exposed areas. Other acids, like Dutch mordant (hydrochloric acid) or vitriol (sulfuric acid), can also be used. After the acid bath, the varnish is removed, the plate is cleaned, and ink is applied to the etched areas. The plate is then printed using a press. Intaglio prints often have a slight gap around the edge (plate mark) and include the artist’s signature, edition number, and other markings.
Aquatint
This technique creates tonal areas instead of lines. A thin layer of asphalt or resin is sprinkled on the plate, then heated. The particles fuse, creating a waterproof layer. Acid is applied, biting into the exposed areas. After removing the asphalt, the plate is inked and printed. Aquatint can also use sugar instead of asphalt, producing a softer, less angular effect.
Sugar Aquatint
Similar to aquatint, this method uses sugar crystals instead of asphalt resin, resulting in a more blurred and warmer effect.
Engraving with Aquatint
Instead of an acid bath, acid is applied with a brush for a milder effect.
Lithography (Planographic Printing)
This process, invented by playwright Alois Senefelder, is closer to painting and drawing. The image is drawn directly onto a porous limestone plate. Greasy materials applied to the stone create the design. A solution of nitric acid and gum arabic is applied, changing the stone’s properties. The greasy areas attract ink, while the non-greasy areas repel it, allowing for printing. Different plates can be used for different colors.
Serigraphy (Screen Printing)
A stencil-based printing technique where ink is forced through a mesh screen onto the printing surface. Areas of the screen are blocked off to create the desired image.
Monotyping
This technique creates a single print from a painted or drawn image on a rigid support while the pigment is still wet. It emphasizes spontaneity. According to the 1960 Vienna Congress, monotypes are considered original prints.
Print Editioning
Original prints are made from the original plate, but they are still considered copies. The artist signs and numbers each print, indicating the edition size. The artist has the exclusive right to determine the final number of prints. After printing, the plates are typically destroyed or marked to prevent further editions. Proofs, such as trial proofs and artist’s proofs, are prints made outside the regular edition.