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Comment peut-on imprimer en 3D des tableaux, qui sont par nature des objets réputés “plats” ?

Je vous propose trois solutions pour l’instant :

• Celle d’un jeune doctorant de l’Université de Delft, vu en 2013 au Digital Heritage Congress à Marseille, Tim Zaman

Il a utilisé trois tableaux, deux Rembrandt et un Van Gogh, qui sont des peintres utilisant de nombreuses couches de peinture, et a mis au point un “scanner 3D” pour la numérisation, puis fait imprimé en 3D le résultat.

Le scanner 3D est constitué de deux Nikon D800E, des appareils photo à 40Mpx, et un projecteur pour aider à la triangulation entre les deux appareils.

L’impression 3D a été confié à une entreprise néerlandaise spécialisée, Océ (Canon Group), qui a non seulement réalisé la forme, mais aussi la couleur des tableaux.

Les tableaux sont donc reproduits à l’identique (ou presque), mais peuvent être observés de près, voire touchés. Ses modèles 3D peuvent permettre aux spécialistes de travailler de très près sans toucher le tableau, voire même sans être près de lui ou dans le même pays. Un double usage qui est très commun à la 3D en général.

Vidéo de la BBC montrant son travail ici.

Vidéo d’une impression 3D en couleur de l’entreprise Océ ici.

Son résumé pour sa présentation au Digital Heritage 2013 à Marseille :

Moving Towards The Ultimate Reproduction – Scanning And Printing of Paintings in High Resolution, Full-Color 3-D.

Paintings are versatile near-planar objects with material characteristics that vary widely. The fact that like sculptures, paint itself also has an important material presence is often overlooked. This is because we have become used to enjoying these artworks through two dimensional media like prints and computer screens. The capture of the topography of the paint in 3-D is not only interesting for study, restoration and conservation, but it also facilitates making three dimensional reproductions through state-of-the-art 3-D printing methods. The design of a 3-D imaging device for paintings is challenging because of their varying material characteristics and subtle depth difference as opposed to the size of the canvas. No single imaging method is ideally suited for this task and each have specific drawbacks.

We propose a hybrid design consisting out of normal studio equipment, where stereo imaging (two cameras) is aided by the fringe projection technique (1 projector). Fringe projection is aided by sparse stereo matching to serve as an image encoder. The encoded images then aid the stereo cameras triangulate each pixel they observe. In this manner, we simultaneously capture both the color and depth, yielding perfect image registration. Through high-end camera’s, special lenses and filters we capture a surface area of 170 square centimeters per capture with an in-plane effective resolution of 50 micron and a depth precision of 9 micron. Semi-automated positioning makes the capture possible of paintings like the 2 square meter big Jewish Bride by Rembrandt, yielding a billion points point-cloud, all labeled with their correct color. Another self-portrait by Rembrandt and work of Van Gogh were also captured to test the performance of the system.

This data is then immediately ready for 3-D printing (the easiest way to visualize huge 3-D models). This was done through a specialized high resolution full color 3-D printer, yielding a very convincing reproduction by accurately portraying the topography.

Sa page ici avec plusieurs vidéos, photos et articles

 

• Celle du projet “Unseen Art”, qui vient tout droit de Finlande

Le projet se propose également d’imprimer en 3D des tableaux, mais d’une façon tout à fait différente : il ne s’agit pas ici de reproduire à l’identique l’œuvre, mais bien d’en créer un rendu 3D.

Et pourquoi pas, de commencer par la Joconde. Le but du projet est d’offrir aux mal-voyants et aux aveugles la chance de pouvoir “voir” certains chef-d’œuvre en touchant leur rendu 3D. Tous les tableaux ne sont pas en relief comme dans le cas de Rembrandt, ou surtout, Van Gogh, et il faut donc créer la tridimensionnalité.

Le projet est expliqué dans cette vidéo.

Site du projet ici.

Page Facebook du projet ici.

Page de l’initiative de financement participatif ici.

 

• Celle mise en œuvre lors de l’exposition “Alchemy de Jackson Pollock. Voyage à l’intérieur de la matière” à la Collezione Peggy Guggenheim de Venise

L’exposition tournait autour du tableau “Alchemy” de Jackson Pollock qui venait de se refaire une beauté à l’Opificio delle Pietre Dure de Florence.

Le Visual Computing Lab de Pise a pour l’occasion réalisé la numérisation du tableau avec un scanner 3D GOM Atos et a fait imprimé en 3D le modèle obtenu par la société spécialisée Océ (Canon Group).

Le modèle a été utilisé pour le public, mais également à des fins scientifiques pour aider la restauration et enrichir l’étude du tableau.

Le choix d’imprimer en 3D le tableau de Jackson Pollock sans couleurs a permis non seulement aux visiteurs de toucher la réplique, mais également de pouvoir en apprécier toute la géométrie en relief sans que l’œil ne soit détourné par les couleurs tour à tour sombres ou éclatantes de l’original.

Extrait de l’article présenté au Digital Heritage 2015 à Grenade :

The possibility to interact and touch this color-stripped reproduction provides an somehow unconventional experience, but lets the user better understand the complexity of the artwork in a completely new way. The printed reproduction was a success, people were at the begin intimidated by the size of it, and the idea of touching an artwork, but soon after the inauguration, all the visitors were happily using the replica.

Page internet de l’exposition ici.

Article présenté au Digital Heritage 2015 à Grenade ici.

 

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Come si può stampare in 3D dei dipinti, che sono per natura oggetti “piatti” ?

Per il momento, vi propongo tre possibilità :

• Quella di un giovane dottorando dell’Università di Delft, visto nel 2013 al Digital Heritage a Marsiglia, Tim Zaman

Ha usato tre dipinti, due Rembrandt ed un Van Gogh, che sono pittori che usano numerosi strati di pittura, ed ha sviluppato uno “scanner 3D” per digitalizzare i capolavori, e poi ha fatto stampare in 3D il risultato.

Lo scanner 3D si costituisce di due Nikon D800E, macchine fotografiche a 40Mpx, ed un proiettore per aiutare alla triangolazione tra le due macchine.

La stampa 3D è stata affidata da una ditta olandese specializzata, Océ (Canon Group), che non solo ha realizzato la stampa della forma, ma anche del colore.

I dipinti sono dunque riprodotti all’identico (o quasi), ma possano essere osservati da molto vicino, addirittura toccati. I modelli 3D possono servire ai specialisti per lavorare da molto vicino senza toccare il dipinto, anzi senza essere accanto o nello stesso paese. Questo doppio uso è molto commune al 3D in generale.

Vidéo della BBC che mostra il suo lavoro qui.

Video di un stampa 3D a colore della ditta Océ qui.

Il riassunto della sua presentazione al Digital Heritage 2013 di Marsiglia :

Moving Towards The Ultimate Reproduction – Scanning And Printing of Paintings in High Resolution, Full-Color 3-D.

Paintings are versatile near-planar objects with material characteristics that vary widely. The fact that like sculptures, paint itself also has an important material presence is often overlooked. This is because we have become used to enjoying these artworks through two dimensional media like prints and computer screens. The capture of the topography of the paint in 3-D is not only interesting for study, restoration and conservation, but it also facilitates making three dimensional reproductions through state-of-the-art 3-D printing methods. The design of a 3-D imaging device for paintings is challenging because of their varying material characteristics and subtle depth difference as opposed to the size of the canvas. No single imaging method is ideally suited for this task and each have specific drawbacks.

We propose a hybrid design consisting out of normal studio equipment, where stereo imaging (two cameras) is aided by the fringe projection technique (1 projector). Fringe projection is aided by sparse stereo matching to serve as an image encoder. The encoded images then aid the stereo cameras triangulate each pixel they observe. In this manner, we simultaneously capture both the color and depth, yielding perfect image registration. Through high-end camera’s, special lenses and filters we capture a surface area of 170 square centimeters per capture with an in-plane effective resolution of 50 micron and a depth precision of 9 micron. Semi-automated positioning makes the capture possible of paintings like the 2 square meter big Jewish Bride by Rembrandt, yielding a billion points point-cloud, all labeled with their correct color. Another self-portrait by Rembrandt and work of Van Gogh were also captured to test the performance of the system.

This data is then immediately ready for 3-D printing (the easiest way to visualize huge 3-D models). This was done through a specialized high resolution full color 3-D printer, yielding a very convincing reproduction by accurately portraying the topography.

La sua pagina qui con video, foto ed articoli.

Articolo sulla Repubblica qui.

 

• Quella del progetto “Unseen Art” che ci viene della Finlandia

Questo progetto proponne anche lui di stampare in 3D dei dipinti, ma in un modo completamente diverso: qua non si tratta di riprodure l’opera all’identico, ma di crearne un modello 3D.

E perchè no, cominciando colla Joconde. L’obiettivo del progetto è di offrire ai ciechi l’opportunità di poter “vedere” alcuni capolavori toccando il loro modello 3D. Non tutti i dipinti sono a rilievo come i Rembrandt, o sopratutto i Van Gogh, quindi bisogna creare la tridimensionalità.

Il progetto viene spiegato in questo video.

Sito del progetto qui.

Pagina Facebook qui.

Pagina della piattaforma di crowdfunding qui.

 

• Quella usata per la mostra “Alchimia di Jackson Pollock. Viaggia attraverso la materia” alla Collezione Peggy Guggenheim di Venezia

La mostra era sul dipinto “Alchemy” di Jackson Pollock, che era appena stato restaurato all’Opificio delle Pietre Dure a Firenze.

Il Visual Computing Lab di Pisa ha per l’occasione realizzato la digitalizzazione del dipinto con uno scanner 3D GOM Atos, e fatto stampare il modello ottenuto dalla ditta specializzata Océ (Canon Group).

Il modello 3D è stato usato per il pubblico, ma anche as uso scientifico per aiutare il restaura ed arrichire lo studio del dipinto.

La scelta di stampare in 3D il dipinto di Jackson Pollock senza i colori non solo ha permesso ai visitatori di poter toccare la replica, ma anche di poter apprezzarne tutta la geometria a rilievo senza che l’occhio sia deviatto dai colori scuri o brillanti dell’originale.

Estratto dell’articolo presentato al Digital Heritage 2015 di Granada:

The possibility to interact and touch this color-stripped reproduction provides an somehow unconventional experience, but lets the user better understand the complexity of the artwork in a completely new way. The printed reproduction was a success, people were at the begin intimidated by the size of it, and the idea of touching an artwork, but soon after the inauguration, all the visitors were happily using the replica.

Site internet della mostra qui.

Articolo presentato al Digital Heritage 2015 di Granada qui.