Fotografia per non vedenti. L’opera di Luigi Ghirri

This paper describes the development of a method for making photographic images usable for the blind. Tactile devices useful for making blind people understand the characteristics of spaces and objects that cannot be described verbally have existed for a long time, especially in kindergarten teaching and in museums. In this work we have focused on the ways in which it is possible to highlight, through an analytical procedure, the main visual elements present in a photograph and on the possibilities of translating them into tactile information. The reduction of three-dimensional space to a flat surface using a perspective view is the basis of the photographic image. The perception of space by a blind person is essentially based on haptics, i.e. the direct and partial tactile perception that the brain then processes into a kinesthetic, synthetic and global apperception of the relationship between one’s body and its surroundings. Having to make the notion of perspective understandable, we created a three-dimensional cubic model on a 1:20 scale of a room with a side of 4 m and removable walls. In it we have inserted four elementary solids. Through the perception of this model, the blind person can experience the characteristics of a space with objects inside it. Starting from the model, we subsequently identified 12 paradigmatic perspective conditions, varying the position of the room, the height, and the distance of the point of view. We then printed a bas-relief of each perspective view, using 5 level curves with a height of 1 mm, to allow the blind person to appreciate how changing the position of the point of view conditions the perspective. In the next step we looked at the visual qualities present in a photo. Some of them can be rendered through a tactile support, regardless of whether they relate to tangible or intangible objects. Other qualities, however, cannot be expressed by a bas-relief. We have identified a total of 31 visual qualities, 15 of which are easily reproduced and 16 whose tactile rendering is more difficult or even impossible. Finally, we applied the method to the work of Luigi Ghirri, an emblematic artist for his constant search for simplicity of composition and forms, the description of everyday spaces and the almost total absence of the human figure; these are characteristics that make the application of the developed method easier. After studying some of his works, we have re-proposed their structure through 5 superimposed horizontal planes, each of which is included in a flat surface protruding 1 mm with respect to the underlying one, similarly to what we saw during the study of the cubic volume. These bas-reliefs, associated with the 3D printing of a schematic three-dimensional model of the environment reproduced in the photo, can allow a blind person to understand some of the compositional choices made by the artist. The application aimed at the production of static basreliefs obviously has a limited scope of application. The development of tactile tablets with rubber screens and motorized spheres will be able to make the development of this mode of representation much simpler and cheaper through the diffusion on the net and the download of digital bas-reliefs.