A retouch invention that is a solution that enables the avoidance of hypothesis to replace the missing parts of the original. 
A theory when retouch becomes a must in cases where the loss of the original substance is so extensive or disturbing that it makes it impossible to perceive the real nature of the artifact. At the same time retouch as an intervention should be easily recognizable to confirm its character of a factor of a potential unity.
Tratteggio may be considered as the discovery of the modern theory of conservation restoration as it was invented according to its guidelines, based on phenomenology and Gestalt philosophy. In this theory the object of art is a sovereign being independent from the reality and completed in its perfection. Independence of this phenomenon excludes the material aspect from its real nature. Creation is a completed action; therefore, the activity of a conservator restorer cannot be creative or imitative in relation to the artist’s work. Nevertheless, in Gestalt the nature of an artifact is described not only by its ‘pristine’ state (in which it was ‘released’ from the artist’s workshop) but also by the later ‘life’ of the artifact. As the substance of the artifact is an example of complete perfection the loss is a foreign body in its integrity.
Types of Tratteggio
An image reintegration method invented and developed in 1945- 50 in Istituto Centrale del Restauro and was inspired by the modern theory of conservation- restoration of Cesare Brandi. Tratteggio as well as its derivatives is a transposition of a representation to the system of vertical lines that, viewed from the distance, form the color (or pattern) that integrates the lacunae with the original. This kind of retouch rebuilds the image and makes it more legible being at the same time apparent and recognizable to the observer. The desired color should be achieved by putting successively the layers of delicate (rather than intensive) color vertical lines.
Selezione Chromatica (selezione del colore, it. ‘chromatic selection’)
a Florentine variant of trattteggio, developed by Ornella Casazza and Umberto Baldini. In selezione the lines may not be vertical but directed according to the image composition. Chromatic selection means finding characteristic features (the elementary colors) of the desired hue and recomposing it by creating the impression of a color that reintegrates the image. Colors in the chromatic selection are put in the layers that when superimposed one onto another work as transparent screens, forming the system of ‘filters’ that give the effect of unified color.
Another Florentine derivative of tratteggio, developed by Ornella Casazza and Umberto Baldini after the flood in Florence in 1966. It was designed to treat the extensive losses in the painting Crucifixion by Cimabue that was seriously damaged in the flood. Astrazione was intended to be used in the situation when it’s not possible to reconstruct the original color. The idea is based on the thesis that there might be a general neutral color that matches to the whole image and provides reintegration and legibility of it. There are limited colors used for the realization of astrazione (primary colors and black). The lines are interweaving and form a vibrant screen of color on the background.
- Tratteggio retouch and its derivatives as an image reintegration solution in the process of restoration Case study : restoration of a 20th century lithograph film poster by Stefan Norblin
- Conservation and authenticity: Interactions and enquiries