Od modelu do modelu. Narracja między rysunkiem a cyfrową reprodukcją ambony Donatella

Sandro Parrinello, Francesca Picchio, Silvia La Placa

doi:10.37190/arc220407

Streszczenie

Celem autorów artykułu było zbadanie narracyjnego i interpretacyjnego wkładu, jaki modele cyfrowe mogą wnieść do archiwizacji dziedzictwa kulturowego. Przedmiotem badań była ambona Donatella w Prato. Ambona ta jest dziełem architektonicznym o wyrafinowanej dekoracji i stanowi miejsce publicznego wystawienia Sacra Cintola (pasa NMP). W katedrze Santo Stefano zachowała się relikwia pasa, który okalał ubranie Dziewicy Maryi. Na głównej fasadzie kościoła umieszczona jest obecnie kopia dzieła Donatella. Oryginalna balustrada przechowywana jest w Muzeum Katedralnym. Obecnie sposoby prezentacji i rozpowszechniania dziedzictwa kulturowego nabierają nowych właściwości wraz z wykorzystaniem i wdrożeniem technologii cyfrowej. Modele 3D oparte na rzeczywistości stają się coraz bardziej dokładnymi kopiami cyfrowymi, które powielają przestrzeń i cechy dzieł architektonicznych, stanowiąc nie tylko kopie, ale także krytyczne reinterpretacje wyrażające formalną syntezę złożoności obiektu. Prowadzone działania dokumentacyjne pozwoliły na wygenerowanie trójwymiarowych baz danych obu ambon, oryginalnej i kopii. Z cyfrowych baz danych opracowano modele 3D oraz modele drukowane, które będą stanowiły dialog na ekspozycji muzealnej renesansowej ambony i jej historii.

Słowa kluczowe:
badanie-3d
cyfrowa-kopia
druk-3d
ambona-donatella

Podgląd pełnego artykułu jest możliwy wyłącznie na większych ekranach.

2022

4(72)

Sandro Parrinello*, Francesca Picchio**, Silvia La Placa***

From Model to Model. The narrative between drawing

and digital reproduction of Donatello’s Pulpit

Reading, interpretation and form

in defining a dialogue

between drawing and model

“It is impossible not to communicate” as Bateson [1],

[2] and the Palo Alto group remind us

, and in commu-

nication, networks of relationships that connect and in-

terconnect are formed. This communication is not only

active, referring back to the systemic paradigm between

individuals, but concerns the continuous ow of inputs

that connects people to things. In this sense, architecture,

environments, spaces and, even more so, artworks, are

participants in this dialogue and this process of interaction.

It is through this dialogue with place [3] that the paradigm

of living is dened, and forms of connection and cultural

dialogue are made possible

. In the age of the digital revo-

lution, the question is how forms, images, data and meta-

data, of a multimedia nature, move the cultural dialogue

ORCID: 0000-0002-3698-7885. Department of Civil Engineer-

ing and Architecture, University of Pavia, Italy.

** ORCID 0000-0002-8072-584X. Department of Civil Engineer-

ing and Architecture, University of Pavia, Italy.

*** ORCID: 0000-0001-9792-9323. Department of Civil Engineer-

ing and Architecture, University of Pavia, Italy, e-mail: silvia.laplaca@

unipv.it

This is the rst of the ve axioms formulated by Gregory Bateson

and other distinguished exponents of the Palo Alto school relating to the

study of communication, its pragmatic function, and verbal and non-

verbal experience in the structuring of messages.

Space talks, and it talks even when we don’t want to hear it

Umber to Eco argued in his introduction to E.T. Hall’s book [3], fore-

shadowing the importance of the dialogue between the individual and

space. On the other hand, in the history of living, building types are

nothing more than the material transguration of how man has thought

about the relationship between physical and social space, how he has

shaped it and how he continually establishes bi-univocal communicative

messages between man and space and space-man.

and change its constituent syntaxes and paradigms

. From

these questions, a dialogue is established and uses the dig-

ital to elaborate a critical thought that actualizes signs and

forms. The problem of the cultural interpretation of lan-

guages is addressed from another perspective [4].

If the drawing is about an artwork, a higher level of

entropy is introduced, and it increases the uniqueness of

the message

The drawing, which is intended to describe a certain

complexity, becomes a critically simplied copy of the

artwork, capable of communicating specic relationships

of the artwork itself. In the drafting of signs, traits and lan-

guage that explicates some of the work’s meanings, a pro-

cess of memorisation is then made explicit. It is therefore

a question of dening languages so that communication

processes are activated and memorisation actions are qual-

Digital neural connections contaminate spaces by animating

dialogues between things (internet of things) and change, through algo-

rithms, the way humans talk to each other, altering the timing of inter-

personal communication.

Each artworks contains dierent messages and communicates in

dierent ways to the user of the message. First and foremost, it is the

author of the work who designs and realises shapes, sounds, or whatever

is necessary to achieve a certain eect. From the sign and gesture of the

author, the work then nds its own identity that surpasses the author’s

message in the multiple readings of the designated audience, the one

for whom the work was created. Then there is the accidental audience,

who in reading the work may misunderstand it, who may not have all

the cultural tools necessary to be able to understand the message and

who, for that reason, reinterpret the artwork. This message deviates even

more if the audience lives in dierent time periods from those in which

the author lived, inevitably modifying any grammar with respect to the

paradigms of their own time. There is then a further message derived

from the digital translation of the work, which corresponds to a synthesis

of all previous levels of interpretation, (which is in any case limited by

the level of interpretation and knowledge of the drawer who transforms

it into digital), and which then dialogues with the digital audience, which

has dierent models and speeds of comparison to establish it.

DOI: 10.37190/arc220407

Published in open access. CC BY NC ND license

72 Sandro Parrinello, Francesca Picchio, Silvia La Placa

ied. This takes place through a dual synergy: the drawing

as an experience, and thus as memory, and the drawing as

a document, which constitutes memory about a narrative.

Reproducing an artwork requires establishing a multi -

tude of dialogues, with the work, with the author of the

work, with the space in which the work is experienced,

and with the user of the work. Drawing a work, then, goes

beyond the simple concept of reproduction, of copying.

Drawing, by its own denition, allows for an interpretation,

simplication of forms, or even transformation of mean-

ings to create, from a work, something “other”.

This contribution aims to describe some drawing activ-

ities conducted on an extremely rened artwork explain-

ing, in addition to the methodological components that de-

ned the actions and activities conducted, the relationship

between the artwork, its copy and its digital copy.

This is a path of knowledge based on drawing, in which

an approach to material and physical knowledge of the

artwork is developed through an analysis of forms and

through processes of measurement [5].

It is therefore a comparative process, more cultural than

strictly dimensional, of recognizing morphometric quali-

ties in relation to measurement units.

The drawing reproduction does not seek to be a sterile

copy, coming from a communication between the drawer

and the artwork. The drawer seeks to weave a dialogue

with the work to elaborate a sign.

The drawing intends to humbly contribute to a specic

analysis, enhancing the forms that characterise the gures

and the decorations drawn. Drawing sets graphic limits

that segmented the continuous nature of the reality.

If a digital drawing represents an artwork, it is relevant

to take into account two aspects for a methodological in-

terpretation. It is necessary to evaluate the more complete

cultural and historical framework in which the drawing is

formed, considering also the goals and the purpose of the

digital activities, and also the nature of the digital draw-

ing, that could be considered as a database

[6].

It is evident that a documentation procedure can only

establish and constitute databases of dierent natures that

dialogue themselves. Based on comparative and analyti-

cal activities, the process is aimed at reproducing forms,

proportions and models in a digital language, creating les

that can be interconnected through several softwares [7].

This is why the process of creating a cognitive database

on Cultural Heritage is a fundamental step to the deni-

tion of a memorisation of the built heritage [8].

Comparative practices between digital and real are

rarely dened through linear continuity. A recursive log-

ical-temporal development constitutes the dialogue. This

is composed by recall, re-proposition, remembrance or re-

ection, rapid analogy, etc. [9].

The communication meaning is mixed with the mean-

ings of knowledge and data archiving. This meaning con-

A 2D or 3D drawing, a critical interpretation of the complexity

of reality, contains a series of coded information in the form of spatial

coordinates or alphanumeric codes that, appropriately selected and orga-

nised, enrich the descriptive potential of the real object, amplifying its

communicative message.

cerns how a certain form of knowledge and archiving

could or should be represented. In digital methods and

tools there are limits concerning the representation. These

limitations of a representation, that being symbolic, also

bring limits to the fundamental notion of meaning.

Through the architectural digital surveying it is possi-

ble to obtain reliable models, in terms of metric data, that

duplicate the environment under investigation. From these

duplicates it becomes possible to develop multiple studies

and analyses, digital simulation to control the develop-

ment of the place predicting activities of design, monitor-

ing, restoration or enhancement [10].

Often instrumental reliability is made to coincide with

me trical accuracy to simplied reproduction of shapes from

real measures. This topic, which does not work in the sci-

ence of architectural representation, could be applied to

have a simplistic qualication of digital models.

Every instant of the modelling process is characterised

by a tension that concerns the approximation of the form,

the denition of the limit. This tension originates a paradox

that is established in the relationship between the precision

of the data, which contemplates the presence of an error,

the denition of a numerical value that qualies a shape

and the adherence between the digital and the real model.

Discretisation, selection and systematisation of the

amount of digital data acquired are procedures aimed at

simplication of the digital model [11]. This simplica-

tion of forms gives the digital model a simplicity to the

advantage of its interconnectivity that makes it an aid to

have precise knowledge because, in some way, it is in-

complete. The notion of completeness concerns the inn-

itesimal limit of imperfection that therefore qualies the

digital model.

The production of technical models, digital and physical

products, is the focus of this research that emphasizes the

practical and applied aspects of digital documentation of

Cultural Heritage. In particular, the focus concerns com-

munication, memorisation, comparison, and knowledge of

digital products, through a series of references and recur-

rences based on the nature of the dierent models obtained.

The allegorical model,

“the invention and the Sacra Cintola narration”

Donatello’s pulpit in Prato constitutes an allegorical

system in relation with Santo Stefano’s Cathedral. It com-

municates the events connected to the city and its relic,

the Sacra Cintola (or Sacred Belt), placed by the apos-

tles around the Virgin’s waist before her assumption into

heaven. The Belt arrived in Prato in 1141, thanks to Mi-

chele Dagomari, a noble from Prato who went to Jeru-

salem on the occasion of the First Crusade (1096–1099).

Dagomari left the relic as a gift to the Pieve di Santo Ste-

fano. The Pieve became an important religious site for

devotees because of the preservation of the Belt [12]. In

the early 1300s the church was enlarged and, in 1428,

the pulpit was built at the intersection of the south and

west elevations of the Cathedral, in a position that ensures

its full visibility from the two squares. Donatello’s pulpit

represents the last stage of the Ostension ritual and from

From Model to Model. The narrative between drawing and digital reproduction of Donatello’s Pulpit 73

this, ve times a year, the bishop shows the Sacra Cintola

to the devotees

(Fig. 1).

The pulpit consists of a structure with a radius of 175 cm,

placed more than 300 cm above the ground. The parapet

is sheltered by an umbrella cover system, above which

there is a statue of Santo Stefano, the patron saint of the

city of Prato.

The circular marble parapet is supported by corbels

and decorative rings and is divided into 7 panels. These

are separated by pairs of uted pilasters with Corinthian

capitals, giving the structure the appearance of a small cir-

cular temple. The tiles host a festive sprites motif, assum-

ing a variety of poses, in a composition characterised by

rhythm and harmony.

Donatello was inspired by the gure of the putto, who

in ancient times was believed to inhabit the paradise of

Dionysus. The sculpted sprites in the pulpit represent both

an icon of the Christian imagination (as they are associat-

ed with the Christian concept of “salvation”) and the sym-

bol of a stylistic and formal revival of classical art desired

by the artist himself.

The ve sprites within each tile are articulated on dif

ferent levels of depth in the joyful dances for the Osten-

sion of the Belt. This three-dimensional and dynamic

eect is made possible by the “stiacciato”, a sculptural

technique with which a relief eect can be achieved with

minimal changes in elevation from the background. This

technique was masterfully used by Donatello to scan the

dierent planes. A background mosaic amplies the sense

of movement thanks to the light eects vibrations, by ac-

companying the Dionysian dances of the festive sprites.

The angular architectural solution has exposed the

pulpit to deterioration over time, including the erosion of

portions of the parapet and the cover system. For these

reasons, the pulpit underwent numerous restorations start-

ing from 1776. In 1972, it was replaced by a copy made of

resin and marble dust, which is today visible on façades

of the Cathedral [13]. The original parapet, together with

the bronze capital below

, is now preserved in the Museo

dell’Opera del Duomo (Fig. 2).

To constitute a digital memory of Donatello’s pulpit,

a digital duplicate has been developed to increase knowl-

edge and communication through a dialogue between

physical and digital models. For this reason, a research

project has been developed to document the original pul-

pit and its outdoor copy [14].

To dene a new dialogue between the artwork and its

reproductions, dierent methodologies and tools have

been tested.

The fast technological evolution applied to Cultural

Heritage increased the accuracy of measuring instruments

updating the databases obtained by digital survey.

The Ostension ritual from Donatello’s pulpit takes place ve ti-

mes a year: on 8 September, for the celebration of the Nativity of the

Virgin, during the Easter period, on 1 May, on 15 August on the occasion

of the Assumption of Mary, and on 25 December.

The bronze capital is the artwork of Michelozzo and probably

Donatello himself. Together with a second capital that was never reali-

sed, it was intended to form the base of the circular crown of the pulpit.

The current databases are characterised by a multiplic-

ity of information that, appropriately discretised, entails

a constant renewal of the narrative and communication of

the work’s values [15].

From such three-dimensional digital products, the drawer

is able to read in detail the texture and imperfections of the

material, its colorimetric component as well as its manu-

facturing process. A processes of analysis, discretisation,

and segmentation of the data obtained must be activated in

relation to the drawing’s communicative purposes.

From a discretised database, numerous interpretative

models of the original artwork can be produced. Thanks to

these models and through the digital, a dialogue between

the work and its duplicates can be enriched, as well as the

relationship between the values of the original work and

the new meanings of its reproductions [16].

The graphic model, “the digital form

and the symbolic reinterpretation”

The integrated survey project for the documentation of

Donatello’s Pulpit have been generated, as well as reliable

databases of the external pulpit and the sculptural parapet

in the Museo dell’Opera del Duomo. From these data-

bases, it is possible to develop graphic models and inter-

pretations able to narrate Donatello’s artwork at dierent

levels of knowledge.

The acquisition campaign on the external pulpit has

been conducted by structuring an integrated acquisition

methodology with laser scanning and photogrammetric

techniques

. This process made it possible to obtain a com-

plete digital database of the metric and material informa-

tion of the artwork. The amount of data collected and in-

tegrated with each other constitutes a real digital duplicate

of the pulpit, visualised in its 3D spatial component and

in its relationship to the Cathedral façade and south ele-

vation (Fig. 3).

This database, if properly integrated in the data and

implemented in the information, allows the structural me-

chanics of the pulpit’s operation to be made explicit in

relation to the building for critical interpretations of the

pulpit. Drawings, elaborated from the databases, help to

make the image of the artwork explicit in its context, both

at general and detailed scale. Two-dimensional represen-

tations of the façades were elaborated to allow compre-

hension of the metric-dimensional and material-qualita-

tive relationships between the pulpit, the cathedral, and

the urban space. These drawings also help to highlight as-

pects that are not immediately visible in the artwork: the

irregularity of certain mouldings, the non-constant step of

the corbels supporting the parapet, the variations (even if

The TLS Faro CAM2 S150 Terrestrial Laser Scanner, the 3D te-

lescopic rod-EYE, two types of drones, both from DJI Enterprise, the

MAVIC 2 PRO and the MAVIC MINI, and the Canon EOS 77D camera

have been used for the documentation of the external pulpit. The indivi-

dual databases that can be obtained from these tools have dierent but

compatible specic characteristics, and can therefore be integrated with

each other. This methodological choice responds to the need to obtain

digital models that are as complete and similar to the original.

74 Sandro Parrinello, Francesca Picchio, Silvia La Placa

Fig. 2. The parapet of Donatello’s

original pulpit, exposed in

the Museo dell’Opera del Duomo,

next to the Santo Stefano Cathedral

in Prato, general view (above),

details (below)

(photo by S. La Placa)

Il. 2. Oryginalna balustrada

kosza ambony Donatella,

eksponowana w Museo

dell’Opera del Duomo,

obok katedry Santo Stefano

w Prato, widok ogólny (u góry),

szczegóły (na dole)

(fot. S. La Placa)

Fig. 1. Donatello’s Pulpit

in Santo Stefano Cathedral

in Prato (left). The two squares

on which the pulpit overlooks

(above right), Cathedral west

façade with the Donatello’s

Pulpit (below right)

(photo by C. Rivellino)

Il. 1. Ambona Donatella

w katedrze Santo Stefano w Prato

(po lewej). Dwa place, na które

wychodzi ambona

(u góry po prawej), fasada

zachodnia katedry z Amboną

Donatella (na dole po prawej)

(fot. C. Rivellino)

minimal) of the elements of the decorative apparatus (dif-

ferences between the decorations on the capitals, between

the pilasters, etc.) (Fig. 4).

The analysis of the drawings and the 3D models pro-

duced by reverse engineering process support consider-

ations on the state of preservation. In particular, thanks

to the analysis of the model, we can appreciate the mor-

phometric variations due to building’s developments and

restoration processes compared to the ideal representation

of the pulpit. Comparisons between the ideal model, the

real model, the copy and the digital model are possible

through dimensional measurement, oering a broader view

of the artwork [17].

The original pulpit parapet is located in the Museum,

placed on a basement 150 cm above the ground. For its

survey, image-based and range-based instruments have

From Model to Model. The narrative between drawing and digital reproduction of Donatello’s Pulpit 75

Fig. 3. The 3D laser scanner point cloud database. The images show the pulpit in its relation to the context of the square and the cathedral,

as well as the processes of partitioning the cloud for

the definition of the representation

planes of the pulpit

(elaborated by S. La Placa)

Il. 3. Skan laserowy 3D na podstawie chmury punktów. Widoki przedstawiają ambonę w jej relacji do kontekstu placu i katedry, a także proces

podziału punktów z chmury dla określenia płaszczyzn reprezentacyjnych ambony (oprac. S. La Placa)

been used, performing at close distances to the surface to

be acquired

Detailed digital duplicates were developed for each

of the parapet tiles. The model obtained has a millimet-

ric-range reliability on the surface rendering of the bas-re-

lief. The integration of the dierent acquisitions generated

models capable of describing the geometry of the elements

and the texture of the material (Fig. 5).

The objective of this survey, designed with graphic res-

titution on a scale of 1:1, was to obtain a highly descrip-

tive database of both the chromatic and geometric com-

ponents of the sculptural apparatus. In particular, thanks

to the use of image-based tools, it was possible to obtain

a photogrammetric model of the entire parapet, with a col-

orimetrically realistic appearance to the original pulpit.

A specic photographic set was set up to capture the co-

lour dierences and lighting eects of the tonal variety of

the mosaic and sculpted surfaces. The set was equipped

with stands, cameras with calibrated lenses and a 24-co-

The Artec Eva was used to further rene the level of metric accura-

cy and textural detail, in addition to the TLS Faro CAM2 S150 Terrestrial

Laser Scanner, and the Canon EOS 77D camera. The Artec Eva is a pre-

cision scanner that, working in structured light, allows creating metrical-

ly accurate and already textured 3D models of medium and small objects

lours colourchecker board for colour adjustment. The

SfM photogrammetric model was appropriately scaled to

the point cloud obtained by a laser scanner. It has been

possible using homologous points, target and physical, in

common between the two databases. The metric reliability

between the two database alignments has been calculated

and veried on the common points. Then, an orthomet-

ric development was carried out on a plane of the pulpit,

obtaining the representation of all elements in “true size”

viewing [18] (Fig. 6).

This aspect of the research was particularly useful

for the design of the museum room in which the pulpit

is located. On the occasion of the temporary exhibition

“Donatello, The Renaissance”, panels III and IV of the

original parapet were removed for display in other inter-

national museums

. The orthomosaic obtained, printed

on a scale of 1:1, replaced the void left by the two tiles,

providing a visual continuity of the entire parapet (Fig. 7).

In parallel, a detailed 3D model of the entire pulpit was

produced using range-based tools. Tiles III and IV were

The museum institutions that will host the two tiles until June

2023 are Palazzo Strozzi and Museo del Bargello in Florence, the State

Museums in Berlin and the Victoria and Albert Museum in London.

76 Sandro Parrinello, Francesca Picchio, Silvia La Placa

digital duplicate of artwork becomes possible from the

processes of mathematical processing for the discretisa-

tion and modelling of data. Such printed reproductions,

which can be quickly and cheaply obtained, represent the

accurate physical copies of the investigated object. The

reliability and correspondence of physical characteristics

between the original, the digital duplicate, and the print-

ed model are aspects that should be veried in relation to

the purpose of use of the prints (visual, tactile, etc.). The

preparation of the 3D model, the choice of printing mate-

rial and the scale at which the object will be printed, are

complex operations. Preliminary operations to prepare for

printing take several times, require numerous print proofs

and tests, and inuence and qualify the relationship be-

tween the original work and the printed product. This di-

alogue between the artwork and its physical copy

passes

selected, optimised and prepared for 3D prototyping. This

process addresses the communicative choice aimed at the

enhancement of the three-dimensional component of Do-

natello’s artwork.

The printed prototype as artwork signifier

Sometimes, digital duplicates or portions of them are

created to nd a tangible conguration of the artwork. Phys-

ical and tactile duplicates take the form of specic com-

municative supports of the artwork that are realised with

a view to more inclusive fruition of the heritage (Fig. 8).

The technological innovations in the eld of 3D scan-

ning documentation of Cultural Heritage nd further use

when combined with the solid prototyping of acquired

objects [19]. Producing three-dimensional prints of the

Fig. 4. 2D drawing processing

obtained from the integration

of range-based and image-based

databases. The drawing shows

the richness and complexity of

the decorative apparatus (details)

of the pulpit, trying to highlight

the peculiarities of the artwork

(elaborated by C. Rivellino)

Il. 4. Przetworzony rysunek 2D,

w wyniku uzyskano integrację

baz danych zasięgowych

i obrazowych. Rysunek ukazuje

bogactwo i złożoność detali

dekoracyjnych ambony,

starając się podkreślić

osobliwości dzieła sztuki

(oprac. C. Rivellino)

From Model to Model. The narrative between drawing and digital reproduction of Donatello’s Pulpit 77

Fig. 5. Range-based data

acquisition of the original

interior pulpit by Artec Eva

instrument. The use of tools

capable of achieving a high level

of detail made it possible

to obtain a metrically and

geometrically responsive 3D

mesh duplicate of the entire

pulpit parapet

(elaborated by H. Fu)

Fig. 5. Akwizycja zasięgowa

danych oryginalnej balustrady

ambony za pomocą instrumentu

Artec Eva. Zastosowanie

narzędzi zdolnych do osiągnięcia

wysokiego poziomu

szczegółowości pozwoliło

uzyskać metrycznie

i geometrycznie dokładną kopię

siatki 3D całej balustrady ambony

(oprac. H. Fu)

through the digital model prepared for printing, that rep-

resents a further synthesis and re-presentation of the real

complexity in a specic heritage review. The tangible

model of the work becomes the expression of a double

dis cre tisation: the rst one, concerning the transition from

the database to the digital model; the second one, con-

cerning the transformation from the digital to the printed

model. These processes are the result of specic technical

and communicative choices, not necessarily in agreement

with those expressed by the original work, but which con-

tribute to giving a new meaning to the printed product.

In the eld of Cultural Heritage, 3D printing nds its

most specic application in museum collections. Sculp-

tures, bas-reliefs, artefacts, mosaics, etc. become 3D tactile

reproductions and, by using this sensory organ, guide the

user towards a new and deeper knowledge of the artistic

and architectural heritage [20]. 3D-printed copies become

objects to actively interact with, useful for understanding

the exhibition route and the functioning of complex sys-

tems. Compared to the original works, they dier in ap-

pearance, colour, materiality and (sometimes) in scale, and

can attract the visitor’s attention throughout the museum.

The digital reconstruction process, developed from the

use of a laser scanner and photogrammetric technologies,

enables non-invasive heritage analysis. When it deals with

prototyping and 3D printing, it oers to museum institu-

tions and, in general, to scholars, the advantage of reliable,

lightweight, manageable and reproducible copies. It is

78 Sandro Parrinello, Francesca Picchio, Silvia La Placa

Fig. 7. Detail of the photographic

image of the SfM model

developed on the plane.

This image was then printed on

a scale of 1:1 on paper

and placed on the basement of

the original pulpit to replace

the void left by tiles III and IV

(elaborated by F. Picchio)

Il. 7. Detal obrazu fotograficznego

modelu SfM opracowanego

na płaszczyźnie. Obraz ten został

wydrukowany w skali 1:1

na papierze i umieszczony

w oryginalnej ambonie w miejsce

pustki pozostawionej przez

płyty III i IV

(oprac. F. Picchio)

Fig. 6. Orthometric development

of the SfM model. Once scaled

and oriented on the basis

of the point cloud obtained from

the terrestrial laser scanner (TLS),

the cylindrical surface of

the photogrammetric model

was developed in the plane

to obtain the true-size tiles

(elaborated by F. Picchio)

Il. 6. Ortometryczne opracowanie

modelu SfM. Po przeskalowaniu

i zorientowaniu na podstawie

chmury punktów z naziemnego

skanera laserowego (TLS),

cylindryczna powierzchnia modelu

fotogrametrycznego została

rozwinięta w płaszczyźnie

w celu uzyskania płyt

o rzeczywistych wymiarach

(oprac. F. Picchio)

From Model to Model. The narrative between drawing and digital reproduction of Donatello’s Pulpit 79

possible to model and produce copies at dierent dimen-

sional scales, maintaining correct proportions and textures

of the material component.

The Donatello pulpit documentation project was an

opportunity to experiment with the use of 3D printing in

the study of the relationship between the original and the

uniqueness of its duplicates.

Both III and IV pulpit tiles intended for museum loan

were digitized and prototyped for 3D printing, enabling

a new type of fruition, visual but also tactile, of the sculp-

tural artwork.

3D printed models, with specic material roughness

suitable for tactile experience, take on a communicative

potential that is more physical than visual. In the case of

the pulpit digitization project, two prints were obtained

from the digital model of tiles III and IV: the rst, light

and manageable on a scale of 1:5, allows an overall view

of the design of the dance of the sprites and helps the un-

derstanding of the structural joints between the panels and

the pilasters; the second, on a scale of 1:1, ensures the

tactile reading by the blind and visually impaired (Fig. 9).

In both cases, the prints were made in white PLA l-

ament, generating a monochrome product. On a visual

level this communicative choice allows to emphasize the

“stiacciato” technique. In fact, the homogeneity of the co-

lour highlighting the shadows and therefore the depth of

the bas-relief. From the point of view of tactile enjoyment,

the monochrome colour of the PLA lament guarantees

minimal dierences in thickness to the touch, which could

be altered by the application of a colour.

The exibility of 3Dprinted products makes them

suitable for several educational purposes and attractive,

interactive and inclusive forms of exhibitions. The cop-

ies obtained are congured as new representative models,

Fig. 8. 3D digital duplicates of the pulpit:

1) laser scanner point cloud of the external pulpit, 2) SfM model of the external pulpit,

3) SfM and textured model of III and IV tiles of the original pulpit,

4) detailed laser scanner model of III and IV tiles of the original pulpit,

5) optimized model of III and IV tiles of the original pulpit for the 3D printing

(elaborated by DAda-LAB research team)

Il. 8. Cyfrowe kopie 3D płyt ambony:

1) chmura punktów oryginalnej ambony ze skanera laserowego, 2) model SfM balustrady kosza oryginalnej ambony,

3) model SfM i teksturowany III i IV płyty oryginalnej ambony,

4) szczegółowy model ze skanera laserowego III i IV płyty balustrady ambony oryginalnej,

5) zoptymalizowany model III i IV płyty balustrady ambony oryginalnej przygotowany do druku 3D (oprac. DAdaLAB research team)

80 Sandro Parrinello, Francesca Picchio, Silvia La Placa

Fig. 10. The exhibition in the hall

of the Museo dell’Opera in which

the original pulpit is presented

stored. It is now possible to

touch the printed panels and

learn about the process that led

from the survey to the 3D

realization through information

panels created for the purpose

(photo by DAda-LAB

research team)

Il. 10. Wystawa w sali Museo

dell’Opera, na której

prezentowana jest oryginalna

ambona. Obecnie można dotknąć

wydrukowanych płyt i zapoznać

się z procesem, który prowadził

od badań do realizacji 3D

poprzez stworzone w tym celu

tablice informacyjne

(fot. DAda-LAB research team)

Fig. 9. Image of the two 3D

printed tiles via solid

prototyping process.

The two tiles joined (above);

the detail of the 3D

printing achieved (below)

(elaborated by DAda-LAB

research team)

Il. 9. Obraz dwóch płyt

w wydruku 3D w procesie

prototypowania bryłowego.

Dwie połączone płytki (powyżej);

szczegół uzyskanego

druku 3D (poniżej)

(oprac. DAda-LAB research team)

From Model to Model. The narrative between drawing and digital reproduction of Donatello’s Pulpit 81

which interpret the original work and increase its accessi-

bility and knowledge, structuring an innovative narrative

and exhibition path (Fig. 10).

Conclusions

The considerations addressed in this contribution un-

derline the importance of integrated digital survey and

documentation for a dual purpose: to develop a database

that can support the conservation of the artwork, and to

create a product that can enrich the cognitive and commu-

nicative value of Cultural Heritage.

The models obtained from the dierent databases can-

not give an exhaustive and complete overview of the origi-

nal artwork. Each model represents a simplied version of

the original but at the same time goes deeper into a specif-

ic descriptive aspect. From dierent products, a plurality

of dierent narratives comes. These oer multiple points

of view: each model is simplied from the original but re-

lated to the other models. This connection provides maxi-

mum personalization of the user’s knowledge experience.

The models and the relationships between them also

become “other” than the artwork itself. These new art-

works enrich the historiographical and historicist debate

on the original one.

The uniqueness and communicative capacity of each

product allow us to consider digital duplicates also as “art-

works in their own right”.

The models express and intend to communicate the in-

trinsic and extrinsic values of the artwork, amplifying the

graphic and infographic corpus, and, acquiring their own

autonomy from the work itself, enrich it with informative

content.

Drawing, together with the documentation processes

that are based on it, makes it possible to organize not only

the production of the model, but also the development of

narrative sequences. These contribute to highlighting pre-

viously unexplored aspects and, consequently, to enhanc-

ing the heritage.

Acknowledgements

The documentation and graphic restitution activities described in this con-

tribution are part of a research project scientically coordinated by the Uni -

versity of Florence and the University of Pavia. The project, nanced by

the Fondazione Cassa di Risparmio di Prato and promoted by the Musei

Diocesani di Prato, was conducted by researchers from the joint laborato-

ry LS3D_Landscape, Survey and Design of the University of Florence and

the University of Pavia and the DAda-LAB laboratory of the Department

of Civil Engineering and Architecture of the University of Pavia.

The nature of dierent duplicates suggests multiple sce-

narios between the tangible and intangible. The rewriting

of artworks in digital environments contributes to the up-

dating of the communicative message. It is also possible to

develop new narrative forms that support and dislocate the

communicative message of the artwork for dierent types

of users.

The provision of augmented and virtual reality appli-

cations enable the creation of settings in which the work

transcends the physical limitations of matter.

The dances of the festive sprites can become dynamic ac-

tions and the architecture of the pulpit can explain the Man-

nerist anticipation that it intimately preserves in its forms.

Tactile prints oriented towards innovative ways of inter-

action with the visitor can be envisaged, diversifying the

opportunities to know the artwork. The digital model sup-

ports the preservation of the memory of the physical model

and, through its interconnectivity, tries to digitally preserve

itself. In the digital transcription of languages, forms, and

models, cultural repercussions are also produced in the

specic territory.

The production of models supports the education in digi-

tal and digital languages. Education takes place by creating

opportunities for comparison that give rise to interactions

and temporal recurrences, in a duplication and replica-

tion of recursive experiences that are stratied over time.

Comparative processes are thus promoted to foster the

development of knowledge and many forms of knowl-

edge, giving rise to models of models.

As in an eternal shining garland, the dream of the pulpit

and the message contained in the artwork, having acquired

matter, are transformed into digital matter. Through the

dream, the model is transformed into new models, which

in their new physicality allow the messages of the past to

be updated and actualized, setting the basis for the me-

chanics of the future.

Translated by

Sandro Parrinello, Francesca Picchio, Silvia La Placa

References

[1] Bateson G., Mente e natura, Adelphi, Milan 1984.

[2] Bateson G., Verso un’ecologia della mente, Adelphi, Milan 1977.

[3] Hall E.T., La dimensione nascosta, Bompiani, Milan 1968.

[4] Ciastellardi M., Le architetture liquide. Dalle reti del pensiero al

pensiero in rete, Edizioni Universitarie di Letture Economia Diritto,

Milan 2009.

[5] Miceli A., Morandotti M., Parrinello S., 3D survey and semantic

analysis for the documentation of built heritage. The case study of

Palazzo Centrale of Pavia University, “Vitruvio” 2020, Vol. 5, No. 1,

65–80, doi: 10.4995/vitruvio-ijats.2020.13634.

[6] Galasso F., Parrinello S., Picchio F., From excavation to drawing

and from drawing to the model. The digital reconstruction of twen-

ty-year-long excavations in the archaeological site of Bedriacum,

“ Journal of Archaeological Science: Reports” 2021, Vol. 35, 102734,

doi: 10.1016/j.jasrep.2020.102734.

[7]

Parrinello S., Picchio F., Database and complexity. Remote use of data

in the virtual space of reliable 3D models, “Architecture and Engine-

ering” 2017, 2(2), 27–36, doi: 10.23968/2500-0055-2017-2-2-27-36.

[8] Parrinello S., Picchio F., Dell’Amico A., When the future is the past.

Database digitali per la virtualizzazione dei beni museali, [in:]

82 Sandro Parrinello, Francesca Picchio, Silvia La Placa

Abstract

From Model to Model.

The narrative between drawing and digital reproduction of Donatello’s Pulpit

The paper aims to consider the narrative and interpretative contribution that digital models can make to heritage archiving date and enhancement,

through an investigation conducted on Donatello’s Pulpit in Prato. The pulpit is an architectural work of sophisticated decoration and constitutes

a stage in the Ostension of the Sacra Cintola ceremony. The relic of the belt that encircled the clothes of the Virgin is preserved in the Cathedral of

Santo Stefano. On the main façade of the church a copy of Donatello’s work is placed. The original opera is kept in the Museum of the same Cathedral.

Today, the modalities of communication and transmission of cultural heritage acquire new features with the use and implemention of digital

technology. Reality-based 3D models become increasingly accurate digital copies that duplicate the space and character of architectural works, con-

stituting not only copies but serving as critical reinterpretations that express a formal synthesis of object complexity.

The documentation activities carried out have made it possible to generate three-dimensional databases of the two pulpits, the original one and

the copy. From digital databases 3D models and printed models have been developed to dialogue in the museum exhibition with the Renaissance

opera and its history.

Key words: 3D survey, digital twin, 3D printing, Donatello’s Pulpit

Streszczenie

Od modelu do modelu.

Narracja między rysunkiem a cyfrową reprodukcją ambony Donatella

Celem autorów artykułu było zbadanie narracyjnego i interpretacyjnego wkładu, jaki modele cyfrowe mogą wnieść do archiwizacji dziedzictwa

kulturowego. Przedmiotem badań była ambona Donatella w Prato. Ambona ta jest dziełem architektonicznym o wyranowanej dekoracji i stanowi

miejsce publicznego wystawienia Sacra Cintola (pasa NMP). W katedrze Santo Stefano zachowała się relikwia pasa, który okalał ubranie Dziewi-

cy Maryi. Na głównej fasadzie kościoła umieszczona jest obecnie kopia dzieła Donatella. Oryginalna balustrada przechowywana jest w Muzeum

Katedralnym.

Obecnie sposoby prezentacji i rozpowszechniania dziedzictwa kulturowego nabierają nowych właściwości wraz z wykorzystaniem i wdroże-

niem technologii cyfrowej. Modele 3D oparte na rzeczywistości stają się coraz bardziej dokładnymi kopiami cyfrowymi, które powielają przestrzeń

i cechy dzieł architektonicznych, stanowiąc nie tylko kopie, ale także krytyczne reinterpretacje, wyrażające formalną syntezę złożoności obiektu.

Prowadzone działania dokumentacyjne pozwoliły na wygenerowanie trójwymiarowych baz danych obu ambon, oryginalnej i kopii. Z cyfrowych

baz danych opracowano modele 3D oraz modele drukowane, które będą stanowiły dialog na ekspozycji muzealnej renesansowej ambony i jej historii.

Słowa kluczowe: badanie 3D, cyfrowa kopia, druk 3D, ambona Donatella

A. Luigini (ed.), #Earth2018. Digital Environments for educa-

tion arts and heritage, Free University of Bolzen, Bolzen 2018,

212–222.

[9] Hofstadter D.R., Gödel, Escher, Bach. Un’eterna ghirlanda bril-

lante, Adelphi, Milan 1990.

[10] Kowalski S., Samól P., Szczepański J., Dłubakowski W., Teaching

architectural history through virtual reality, “World Transactions

on Engineering and Technology Education” 2020, Vol. 18, No. 2,

197–202.

[11] Acampa G., Grasso M., Heritage evaluation: restoration plan

through HBIM and MCDA, “IOP Conference Series: Materials

Science and Engineering” 2020, 949 012061, doi: 10.1088/1757-

899X/949/1/012061.

[12] Dello Russo M., Storia della Sacra Cintola di Prato, Stamperia

Ferrante, Naples 1858.

[13] Giusti A., Biliotti C., “… sì belli e sì mirabili”: recuperi e limiti

nel restauro dei rilievi donatelliani, [in:] A. Giusti (ed.), Donatello

restaurato. I marmi del pulpito di Prato, Maschietto Editore, Flo-

rence 2000, 61–72.

[14] Rivellino C., Ricciarini M., Testing the reliability of mini-UAVs ac-

quisition campaign on detailed bas-reliefs. The case study of sculp-

turing elements of Donatello’s Pulpit, [in:] S. Barba, S. Parrinello,

A. di Filippo, A. Dell’Amico (eds.), D-SITE Drones – Systems of

Information on cultural heritage, Pavia University Press, Pavia

2022, 518–527.

[15]

Parrinello S., De Marco R., Galasso F., Un protocollo di modella-

zione urbana mediante abachi e modulo tecnologici. Dal rilievo di-

gitale al sistema informativo 3D per il centro storico di Betlemme,

[in:] T. Empler, A. Caldarone, A. Fusinetti (eds.), 3D

MODELING &

BIM. Data Modeling & Management for AECO Industry, Sapienza

Università di Roma, Tipograa Del Genio Civile, Roma 2020, 62–83.

[16] Parrinello S., Dell’Amico A., Experience of documentation for the

accessibility of widespread cultural heritage, “Heritage” 2019,

2(1), 1032–1044, doi: 10.3390/heritage2010067.

[17] Bruzelius C., Digital technologies and new evidence in architec-

tural history, “Journal of the Society of Architectural Historians”

2017, Vol. 76, No. 4, 436–439.

[18] Pancani G., Piazza dei Miracoli a Pisa: il Battistero. Metodologie

di rappresentazione e documentazione digitale 3D, EDIFIR, Flo-

rence 2016.

[19] Jung T.H., tom Dieck M.C., Augmented reality, virtual reality and

3D printing for the co-creation of value for the visitor experien-

ce at cultural heritage places, “Journal of Place Management and

Development” 2017, Vol. 10, Iss. 2, 140–151, doi: 10.1108/JPMD-

07-2016-0045.

[20] Fu H., Le stampe 3D per una fruizione tattile delle sepolture, [in:]

B. Bruno, E. Napione, F. Picchio (ed.), I Mondiali di Italia ’90

e la scoperta della necropoli romana. Un progetto espositivo per

il trentennale della scoperta della necropoli di Porta Palio, Pavia

University Press, Pavia 2022, 99–105.