Una mirada retrospectiva a les restauracions antigues III. El jaciment d’Akrotiri a l’illa de Santorini, Grècia

El jaciment d’Akrotiri a l’illa de Santorini, conegut com la “Pompeia de l’Egeu”, per haver quedat sepultat per la lava d’una gran erupció volcànica durant l’Edat de Bronze i que la cultura popular associa amb el mite de l’Atlàntida, és un dels pocs jaciments arqueològics on conservació i restauració han tingut des del començament un paper determinant en el protocol d’excavació. La necessitat de conservar les restes per exposar-les al públic, mantenint l’aire d’autenticitat del conjunt, el fan un exemple poc corrent des del qual valorar la disjuntiva d’excavar fins a conèixer abastament un jaciment, o reduir les intervencions arqueològiques al mínim per centrar-se en l’estudi, publicació i exposició del material

Computer–Aided Reassembly of Fragmented Wall Painting

U Sloveniji postoji nekoliko bogatih arheoloških nalazišta iz rimskog razdoblja. Kao primjer takva nalazišta valja spomenuti antički grad Celeiu, čiji se ostaci nalaze na području današnjeg Celja. 1978. godine, tijekom preuređenja ugostiteljskog objekta Turška mačka provedena su arheoloških iskopavanja te pronađeni ostaci rimske vile iz 3. stoljeća. Na lokalitetu je, među ostalim nalazima, otkriven i neobično velik broj fragmenata zidnih slika, različitih veličina, boja i uzoraka. Fragmenti su 1989. godine preneseni u ljubljanski Restauratorski centar ZVKDS, no uslijed neprimjerenih uvjeta za pohranu i ograničenoga radnog prostora, nastojanja da ih se sastavi nisu polučila uspjeh. Budući da fragmente karakteriziraju jedinstveni motivi i dobra očuvanost, projekt je nastavljen 2009. godine, primjenom posve novoga pristupa. U nastojanju da se omogući sveobuhvatan uvid u fragmente te ubrza postupak rekonstrukcije izvorne slike, donesena je odluka da ih se digitalizira te razvije 2D kompjutorska podrška. Na poleđinu svakog fragmenta pričvršćen je jedinstveni osmeroznamenkasti broj kako bi se olakšao proces identifikacije. Pojedinačni su dijelovi snimljeni, čime je utvrđen točan broj fragmenata (9 522 ulomaka). Kako bi se oblikovao virtualni okoliš za sastavljanje ulomaka, skenirana/fotografirana je njihova oslikana strana. Slike ulomaka zatim su digitalno obrađene i unesene u program za digitalnu rekonstrukciju. Sam program (Pedius) ne predlaže rješenja za rekonstrukciju već služi kao baza ulomaka iz koje se oni mogu pojedinačno izlučivati prema različitim kriterijima. Kako bi se stručnjacima uštedjelo vrijeme utrošeno na digitalno sastavljanje fragmenata, razvijena je mobilna i mrežna aplikacija (e-Pedius) u obliku napredne inačice osnovnog programa. Aplikacija je osmišljena kao igra sastavljanja fragmenata koja istovremeno pruža osnovne informacije o kulturnoj baštini. Pedius, isto kao i e-Pedius, pokazali su se vrlo korisnim alatima. Ustanovljeni su, međutim, i određeni problemi, poput loše vidljivosti uslijed ograničenja u rezoluciji te nepostojanja treće dimenzije (debljina žbuke i eventualne pukotine). U procesu same rekonstrukcije kao referenca je korištena digitalna kompozicija ulomaka te njihov popis. Postupak rekonstrukcije odvijao se u ad hoc sastavljenom pješčaniku (3 × 4 m) ispunjenom kuglicama od ekspandirane gline. Tijekom tog je procesa veličina motiva planiranog za muzejsku prezentaciju porasla s izvornih 1 × 3 m na više od 3 × 4 m. Dio koji smo uspjeli rekonstruirati pokazao se doista jedinstvenim; tako bogatu kompoziciju velikih dimenzija iz rimskog razdoblja u Sloveniji rijetko možemo naći. Upravo je zato uložen znatan napor kako bi se široj javnosti omogućio uvid u ovaj izniman primjer kulturne baštine.In Slovenia, some rich archaeological sites with remains from the ancient Roman era can be found. As an example of such a site, the ancient town of Celeia should be mentioned. Remains of this ancient town are located in the area of today’s city of Celje. In 1978, during an archaeological research, remains of a Roman villa from the third century were found while an inn then named Turška Mačka was being demolished. Among other finds, an incredibly large number of wall painting fragments were discovered on the site. In 1989, these fragments of various sizes, colours and patterns were delivered to the Ljubljana Restoration Centre. Because of the inappropriate conditions and limited workspace at that time, an attempt to reassemble the fragments was unsuccessful. Since the fragments exhibited unique motifs and a well-preserved condition, the project was resumed in 2009, applying a completely new approach. In an effort to provide a comprehensive overview of the fragments and accelerate the process of reassembling the original painting, a decision was made to digitize the fragments and develop computer support. A program developed for recording the fragments and supporting the process of reassembly, as well as the mobile version of the program, proved to be very useful. However, certain shortcomings were also discovered – mainly during the phase of actual reassembly

Example-Based Fractured Appearance

International audienceA common weathering effect is the appearance of cracks due to material fractures. Previous exemplar-based aging and weathering methods have either reused images or sought to replicate observed patterns exactly. We introduce a new approach to exemplar-based modeling that creates weathered patterns on synthetic objects by matching the statistics of fracture patterns in a photograph. We present a user study to determine which statistics are correlated to visual similarity and how they are perceived by the user. We then describe a revised physically-based fracture model capable of producing a wide range of crack patterns at interactive rates. We demonstrate how a Bayesian optimization method can determine the parameters of this model so it can produce a pattern with the same key statistics as an exemplar. Finally, we present results using our approach and various exemplars to produce a variety of fracture effects in synthetic renderings of complex environments. The speed of the fracture simulation allows interactive previews of the fractured results and its application on large scale environments

A Survey of Geometric Analysis in Cultural Heritage

We present a review of recent techniques for performing geometric analysis in cultural heritage (CH) applications. The survey is aimed at researchers in the areas of computer graphics, computer vision and CH computing, as well as to scholars and practitioners in the CH field. The problems considered include shape perception enhancement, restoration and preservation support, monitoring over time, object interpretation and collection analysis. All of these problems typically rely on an understanding of the structure of the shapes in question at both a local and global level. In this survey, we discuss the different problem forms and review the main solution methods, aided by classification criteria based on the geometric scale at which the analysis is performed and the cardinality of the relationships among object parts exploited during the analysis. We finalize the report by discussing open problems and future perspectives

Fracturing artefacts into 3D printable puzzles to enhance audience engagement with heritage collections

Three-dimensional (3D) puzzles of heritage artefacts are typically used to engage audiences in the interpretation of archaeological objects in a museum gallery. The reason for this is that a puzzle can be seen as an enjoyable educational activity in the form of a game but also as a complex activity that archaeologists undertake when re-assembling fragments, for instance, of broken pottery. Until now the creation of this type of experiences is mostly a manual process and the artefacts used rarely reflect those in the collection due to the complex nature of the process. The contribution of this article is a novel digital worfklow for the design and fabrication of 3D puzzles that overcomes these limitations. The input to the workflow is an authentic artefact from a heritage collection, which is then digitised using technologies such as 3D scanning and 3D modelling. Thereafter, a puzzle generator system produces the puzzle pieces using a cell fracture algorithm and generates a set of puzzle pieces (female) and a single core piece (male) for fabrication. Finally, the pieces are fabricated using 3D printing technology and post-processed to facilitate the puzzle assembly. To demonstrate the feasibility of the proposed novel workflow, we deployed it to create a puzzle activity of the Saltdean urn, which is exhibited at the Archaeology Gallery of the Brighton Museum and Art Gallery. The workflow is also used with further artefacts to demonstrate its applicability to other shapes. The significance of this research is that it eases the task of creating puzzle-like activities and maintaining them in the long term within a busy public space such as a museum gallery

Electronic Imaging & the Visual Arts. EVA 2019 Florence

The Publication is following the yearly Editions of EVA FLORENCE. The State of Art is presented regarding the Application of Technologies (in particular of digital type) to Cultural Heritage. The more recent results of the Researches in the considered Area are presented. Information Technologies of interest for Culture Heritage are presented: multimedia systems, data-bases, data protection, access to digital content, Virtual Galleries. Particular reference is reserved to digital images (Electronic Imaging & the Visual Arts), regarding Cultural Institutions (Museums, Libraries, Palace - Monuments, Archaeological Sites). The International Conference includes the following Sessions: Strategic Issues; New Science and Culture Developments & Applications; New Technical Developments & Applications; Cultural Activities – Real and Virtual Galleries and Related Initiatives, Access to the Culture Information. One Workshop regards Innovation and Enterprise. The more recent results of the Researches at national and international level are reported in the Area of Technologies and Culture Heritage, also with experimental demonstrations of developed Activities

Transfer zidnog oslika vijenca iz renesansne kuće Moise u Cresu te recentna praksa transfera

Transfer je najinvazivniji postupak konzerviranja-restauriranja zidnih slika. U ovom diplomskom radu opisane su sve etape postupka transfera: od donošenja odluke o izvedbi postupka, preko pripreme zidne slike za odvajanje te odvajanja od izvornog nosača, do obrade te postavljanja zidne slike na novi nosač. Tehnika izvođenja transfera značajno je napredovala u odnosu na svoje početke. Specijaliziraniji materijali i tehnike koji se upotrebljavaju pri ovom postupku od druge polovice 20. stoljeća omogućuju konzervatorima-restauratorima bolju kontrolu postupka te povećavaju izglede za njegovu uspješnu provedbu. U radu su opisani moderni materijali i tehnike, prema redoslijedu etapa postupka transfera. Materijali su podijeljeni prema namjeni i kemijskom sastavu, a njihova je primjena potkrijepljena primjerima iz svjetske prakse u 21. stoljeću. Glavna tema i cilj ovog rada bila je obrada fragmenta zidne slike odvojenog od izvornog nosača te njegovo postavljanje, odnosno vraćanje, zajedno s novim, pokretnim nosačem, na izvorni položaj in situ. Fragment u pitanju dio je zidnog oslika vijenca, datiranog u 16. stoljeće, koji se nekada prostirao duž sviju zidova središnjeg salona prvog kata renesansne kuće Moise u Cresu. Kuća Moise je renesansna palazetta creskog plemstva koja je kroz godine doživjela mnoge pregradnje i preinake. U sklopu brojnih adaptacija kuće, njen je interijer mnogo puta mijenjan te ukrašavan zidnim oslicima iz različitih razdoblja čiji se tragovi i danas u njoj nalaze. Prilikom temeljite adaptacije kuće Moise, koja je započela 2010. godine s ciljem prenamjene u Sveučilišni istraživački centar i regionalni centar za cjeloživotno učenje, 2016. godine ustanovljen je problem statičke nestabilnosti južnog dijela zapadnog zida na prvom katu kuće, na kojem se, u njegovoj gornjoj zoni, prostirao vrijedan renesansni oslik vijenca. Nestabilan zid na kojem se nalazio oslik predodređen je za rušenje, što je uvjetovalo potrebu za odvajanjem spomenutog fragmenta. Fragment oslika vijenca odvojen je od izvornog nosača u tri dijela te predan na daljnju obradu diplomanticama Odsjeka za konzerviranje i restauriranje umjetnina Akademije likovnih umjetnosti u Zagrebu, Ivani Dragozet i autorici ovog rada. Obrada triju dijelova odvojenog fragmenta zidnog oslika sastojala se od obrade žbuke na poleđini, uklanjanja privremenog nosača, nanošenja backinga, ponovnog spajanja u cjeloviti fragment te postavljanja cjelovitog fragmenta na prijenosni nosač. U okviru diplomskoga rada, tako obrađen fragment postavljen je na svoj izvorni položaj u kući Moise. S lica fragmenta potom je uklonjen facing, izrađene su žbukane nadoknade u sloju intonaca te prijedlog za buduću izvedbu nadoknada u slikanom sloju. Prije spomenutih zahvata napravljene su probe određenih postupaka uporabom odabranih materijala te su simulirane glavne etape obrade. Sve navedene etape izvršene su te je fragment zidne slike uspješno vraćen na svoj izvorni položaj u kući Moise. U budućnosti se planira povezati oslik fragmenta s ostatkom oslika vijenca očuvanog na zidovima nekadašnjeg središnjeg salona. To će se postići djelomičnom rekonstrukcijom geometrijskih elemenata (obrisa iluzionistički slikanih profilacija) između odvojenog fragmenta na južnom i ostatka oslika na sjevernom dijelu zapadnog zida.Transfer of wall paintings is the most invasive procedure in the conservation of wall paintings. In this diploma thesis, the stages of the process of transfer are described: starting from the decision of inevitability of detachment of a wall painting, trough the stages of its preparation for detachment, followed by the detachment itself. Furthermore, post-detachment operations, which lead to mounting of the detached painting onto a new support are described, as well as the final presentation. Transfer techniques have developed significantly throughout the history. Specialised materials and techniques that have been implemented in this procedure since the second half od the 20th century, allow better control and increase the probability of a successful treatment. In this thesis, modern materials and techniques are described in order and based on the way they are used in certain stages of the procedure. The materials mentioned are arranged by their purpose and chemical composition. Examples of their use are presented in the descriptions of the specific cases of transfer of wall paintings conducted in the 21th century. The focus of this thesis was the procedure of re-mounting of a detached wall painting fragment. The conservation work consisted of treatments which allowed mounting of the detached fragment on a movable support and finally on a newly built wall. The fragment in question is a part of the 16th century painted frieze decoration situated in the central salon on the first floor of the renaissance palace Moise on the island of Cres. Moise palace is a renaissance patrician residence, so called palazzetta, which has undergone many changes in terms of architectural renovation throughout the history. Its interior walls are decorated with various chronological layers of wall paintings, reminiscent of those adaptations. The Moise palace was in poor state of conservation and it was decided that it would be renovated and repurposed in a University research centre and lifelong learning regional centre. The extremely complex project started in the year 2010. In the year 2016 problems with static stability of the wall carrying the wall painting fragment were discovered. The supporting wall had to be demolished and replaced by a new one, which meant that the wall painting it carries needed to be quickly detached in order to be preserved. The painting was divided into 3 smaller sections, detached from its original support and was then given for further conservation treatments to two graduate students of the Department for Conservation and Restoration of Works of Art (Academy of Fine Arts, University of Zagreb) - Ivana Dragozet and the author of this thesis. Conservation work on the three sections of the wall painting fragment consisted firstly of thinning of the plaster on the backside of sections, removal of the temporary support and application of backing. Secondly, the three sections were re-connected into the whole, the connected fragment was mounted on a movable support, transported and re-mounted in its original position on a newly built wall in the Moise palace. Upon re-mounting, the facing was removed from the surface of the wall painting and inadequate plaster fillings were replaced. Finally, the conservation work was concluded with propositions for the final presentation i.e. reintegration of the missing paint layer. For this purpose a few test areas were made. The conservation project was carried out successfully. The re-mounted wall painting fragment is yet to be connected to the rest of the painted frieze via geometrical reconstruction of the missing parts of the paint layer

Transfer zidnog oslika vijenca iz renesansne kuće Moise u Cresu te recentna praksa transfera

Transfer je najinvazivniji postupak konzerviranja-restauriranja zidnih slika. U ovom diplomskom radu opisane su sve etape postupka transfera: od donošenja odluke o izvedbi postupka, preko pripreme zidne slike za odvajanje te odvajanja od izvornog nosača, do obrade te postavljanja zidne slike na novi nosač. Tehnika izvođenja transfera značajno je napredovala u odnosu na svoje početke. Specijaliziraniji materijali i tehnike koji se upotrebljavaju pri ovom postupku od druge polovice 20. stoljeća omogućuju konzervatorima-restauratorima bolju kontrolu postupka te povećavaju izglede za njegovu uspješnu provedbu. U radu su opisani moderni materijali i tehnike, prema redoslijedu etapa postupka transfera. Materijali su podijeljeni prema namjeni i kemijskom sastavu, a njihova je primjena potkrijepljena primjerima iz svjetske prakse u 21. stoljeću. Glavna tema i cilj ovog rada bila je obrada fragmenta zidne slike odvojenog od izvornog nosača te njegovo postavljanje, odnosno vraćanje, zajedno s novim, pokretnim nosačem, na izvorni položaj in situ. Fragment u pitanju dio je zidnog oslika vijenca, datiranog u 16. stoljeće, koji se nekada prostirao duž sviju zidova središnjeg salona prvog kata renesansne kuće Moise u Cresu. Kuća Moise je renesansna palazetta creskog plemstva koja je kroz godine doživjela mnoge pregradnje i preinake. U sklopu brojnih adaptacija kuće, njen je interijer mnogo puta mijenjan te ukrašavan zidnim oslicima iz različitih razdoblja čiji se tragovi i danas u njoj nalaze. Prilikom temeljite adaptacije kuće Moise, koja je započela 2010. godine s ciljem prenamjene u Sveučilišni istraživački centar i regionalni centar za cjeloživotno učenje, 2016. godine ustanovljen je problem statičke nestabilnosti južnog dijela zapadnog zida na prvom katu kuće, na kojem se, u njegovoj gornjoj zoni, prostirao vrijedan renesansni oslik vijenca. Nestabilan zid na kojem se nalazio oslik predodređen je za rušenje, što je uvjetovalo potrebu za odvajanjem spomenutog fragmenta. Fragment oslika vijenca odvojen je od izvornog nosača u tri dijela te predan na daljnju obradu diplomanticama Odsjeka za konzerviranje i restauriranje umjetnina Akademije likovnih umjetnosti u Zagrebu, Ivani Dragozet i autorici ovog rada. Obrada triju dijelova odvojenog fragmenta zidnog oslika sastojala se od obrade žbuke na poleđini, uklanjanja privremenog nosača, nanošenja backinga, ponovnog spajanja u cjeloviti fragment te postavljanja cjelovitog fragmenta na prijenosni nosač. U okviru diplomskoga rada, tako obrađen fragment postavljen je na svoj izvorni položaj u kući Moise. S lica fragmenta potom je uklonjen facing, izrađene su žbukane nadoknade u sloju intonaca te prijedlog za buduću izvedbu nadoknada u slikanom sloju. Prije spomenutih zahvata napravljene su probe određenih postupaka uporabom odabranih materijala te su simulirane glavne etape obrade. Sve navedene etape izvršene su te je fragment zidne slike uspješno vraćen na svoj izvorni položaj u kući Moise. U budućnosti se planira povezati oslik fragmenta s ostatkom oslika vijenca očuvanog na zidovima nekadašnjeg središnjeg salona. To će se postići djelomičnom rekonstrukcijom geometrijskih elemenata (obrisa iluzionistički slikanih profilacija) između odvojenog fragmenta na južnom i ostatka oslika na sjevernom dijelu zapadnog zida.Transfer of wall paintings is the most invasive procedure in the conservation of wall paintings. In this diploma thesis, the stages of the process of transfer are described: starting from the decision of inevitability of detachment of a wall painting, trough the stages of its preparation for detachment, followed by the detachment itself. Furthermore, post-detachment operations, which lead to mounting of the detached painting onto a new support are described, as well as the final presentation. Transfer techniques have developed significantly throughout the history. Specialised materials and techniques that have been implemented in this procedure since the second half od the 20th century, allow better control and increase the probability of a successful treatment. In this thesis, modern materials and techniques are described in order and based on the way they are used in certain stages of the procedure. The materials mentioned are arranged by their purpose and chemical composition. Examples of their use are presented in the descriptions of the specific cases of transfer of wall paintings conducted in the 21th century. The focus of this thesis was the procedure of re-mounting of a detached wall painting fragment. The conservation work consisted of treatments which allowed mounting of the detached fragment on a movable support and finally on a newly built wall. The fragment in question is a part of the 16th century painted frieze decoration situated in the central salon on the first floor of the renaissance palace Moise on the island of Cres. Moise palace is a renaissance patrician residence, so called palazzetta, which has undergone many changes in terms of architectural renovation throughout the history. Its interior walls are decorated with various chronological layers of wall paintings, reminiscent of those adaptations. The Moise palace was in poor state of conservation and it was decided that it would be renovated and repurposed in a University research centre and lifelong learning regional centre. The extremely complex project started in the year 2010. In the year 2016 problems with static stability of the wall carrying the wall painting fragment were discovered. The supporting wall had to be demolished and replaced by a new one, which meant that the wall painting it carries needed to be quickly detached in order to be preserved. The painting was divided into 3 smaller sections, detached from its original support and was then given for further conservation treatments to two graduate students of the Department for Conservation and Restoration of Works of Art (Academy of Fine Arts, University of Zagreb) - Ivana Dragozet and the author of this thesis. Conservation work on the three sections of the wall painting fragment consisted firstly of thinning of the plaster on the backside of sections, removal of the temporary support and application of backing. Secondly, the three sections were re-connected into the whole, the connected fragment was mounted on a movable support, transported and re-mounted in its original position on a newly built wall in the Moise palace. Upon re-mounting, the facing was removed from the surface of the wall painting and inadequate plaster fillings were replaced. Finally, the conservation work was concluded with propositions for the final presentation i.e. reintegration of the missing paint layer. For this purpose a few test areas were made. The conservation project was carried out successfully. The re-mounted wall painting fragment is yet to be connected to the rest of the painted frieze via geometrical reconstruction of the missing parts of the paint layer