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reasons for its continued importance. What does it mean to enshrine an original, if
the contemplation of its auratic quality is impossible? This, too, is another element
that can be prized away and distinguished from all the others. Actually, this
component of originality does not need to go with the originality of the location:
the best proof of this may lie in the facsimile of the burial chamber from the Tomb
of Thutmosis III in the Valley of the Kings.
5
It contains the first complete text of
the Amduat to be used in a pharaonic tomb. The Amduat is a complex narrative
mixing art, poetry, science and religion to provide a coherent account of life in the
afterworld. The tomb was never made to be visited and the physical and climatic
conditions inside the tomb are incompatible with mass tourism. As a result, the
tomb is deterioriating rapidly and glass panels have had to be installed to protect
the walls from accidental damage and wear and tear. However, the interventions
in the tomb change its nature and inhibit both detailed study of the text and an
appreciation of the specific character of the place. Exhibitions that present the
facsimile and contextualize the text have now been visited by millions of people in
North America and Europe. The delocalized facsimile has established the reasons
for its continued importance, turned the visitors into a pro-active force in the
conservation of the tomb, and could become part of a long term policy that will
keep the version n-1 safe but accessible to the small number of specialists who
require access for continued study and monitoring. See? Each of the components
that together comprise what we mean by a true original begin traveling at
different speeds along the trajectory and begin to map out what we have called the
catchment area of a work of art.
A third element of originality has to do with the surface features of a work.
Too often, restorers make a mockery of the materiality of the original they claim
to protect by limiting matter to shape only because they confuse 3D with 2D. If
there is one aspect of reproduction that digital techniques have totally modified, it
is certainly the ability to register the most minute three dimensional aspect of a
work without putting the work at risk. It is often forgotten that in its early years the
British Museum used to take plaster casts of their objects and the first British
Museum catalogue contained a list of copies that were available and for sale. It is
often forgotten because the plaster cast collection was discarded at the end of the
20th century and valuable information about the surface of works when they
entered the museum was lost. Many of the moulds still contained the paint that
was removed during the casting process and subsequent restorations of the
originals have dramatically altered the surface and appearance of many of the
objects. So, even for a work of art to be material is a question of complex
trajectories. Many Venetians, when they first heard of the Nozze fac simile,
5
The facsimile of the tomb (in its current condition but without the elements that turn
the environment into a museum) has resulted in detailed publications by the egyptologist
Erik Hornung and the psychologist Theodor Abt in both film and book form.
Hornung, Erik and Abt, Theodor. The Dark Hours of the Sun -- The Amduat in the tomb of
Thutmose III, DVD, Pubished by Factum Arte , 2005
Hornung, Erik and others. Immortal Pharaoh- the tomb of Thutmose III. Madrid, Factum
Arte, 2006
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immediately conjured up in their mind a glossy flat surface much like that of a
poster, and they were horrified at the idea of being given this in reparation for
Napoleon's cultural rape of San Giorgio. Little could they anticipate that the
facsimile was actually in pigment on a canvas coated with gesso, "just like"
Veronese had used. When it was unveiled, there was a moment of silence, then
ecstatic applause and many tears. Large numbers of Venetians had to ask
themselves a very difficult question: how is it possible to have an aesthetic and
emotional response in front of a copy? This question is followed by another: how
do we stop Venice from being flooded with bad copies without the criteria to
distinguish between good and bad transformations?
Once again, digital techniques allow us to distinguish features that are
being regrouped much too quickly into the generic term "reproduction". As we
have seen, exactly the same intellectual oversimplifications and category mistakes
happened when Benjamin wrote about "mechanical reproduction". Surely the
issue is about accuracy, understanding and respect - the absence of which results
in "slavish" replication. The same digital techniques may be used either slavishly
or originally. It depends again on what features one chooses to bring into focus
and which ones are left out. The use of tiny painted dots based on photographs
rather than the broader brush marks used to make the original may give the
restorer more control and hide the interventions but surely it proves that a manual
reproduction might be infinitely more disputable and subjective than any
"mechanical" one. The road to hell is paved with good intentions.
No doubt, it is an uphill battle: facsimiles have a bad reputation —people
assimilate them with a photographic rendering of the original— and digital is
associated with an increase in virtuality. So, when we speak of "digital facsimiles",
we are certainly looking for trouble. And yet we claim that, contrary to common
presuppositions, digital facsimiles are introducing many new twists into the
century old trajectory of works of art. There is nothing especially "virtual" in
digital techniques —and actually there is nothing entirely digital in digital
computers either!
6
The association of digitality with virtuality is entirely due to the
bad habits given by only one of its possible outputs: the pretty poor screen of our
computers. Things are entirely different when digital techniques are only one
moment in the move from one material entity—Veronese' Nozze version n-1 in Le
Louvre—to another equally material entity—version n +1 in San Giorgio. During
this time of mass tourism, increasingly vocal campaigns for the repatriation of
spoils of wars or commerce, when so many restorations are akin to iconoclasm,
when the sheer number of amateurs threaten to destroy even the sturdier pieces in
the best institutions, it does not require excessive foresight to maintain that digital
facsimiles offer a remarkable new handle to give to the notion of originality what is
6
Lowe, Adam, and Simon Schaffer. N01se, 2000. An Exhibition Held Simultaneously
at Kettle´s Yard, the Whipple Museum of the History of Science, Cambridge, the
Museum of Archaeology and Anthropology, Cambridge and the Wellcome Institute,
London. Cambridge: Kettle's Yard, 2000; Smith, Brian Cantwell. Digital Abstraction and
Concrete Reality. In Impressiones, Calcografia Nacional, Madrid, 2003.
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required by the new time. Since all originals have to be reproduced anyway,
simply to survive, it is crucial to be able to discriminate between good and bad
reproductions.
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APPENDIX
The process used to create an accurate facsimile of Les Noces de
Cana by Paolo Caliari (called Véronèse).
Adam Lowe
In the autumn of 2006, the Musée du Louvre reached an agreement with
Fondazione Giorgio Cini and granted Factum Arte access to record Veronese's
vast painting Les Noces De Cana. The conditions were carefully specified: the
recording must be completely non-contact, all equipment must meet the highest
conservation specifications and be approved prior to use in the museum, no
external lighting or scaffolding could be used, work could only happen when the
museum was closed and no equipment could be left in the room when the public
was present. In defining each condition the safety of the painting (and the other
paintings in the room) was always the decisive factor.
To record this 67.29 square meter painting at actual size and at the highest
possible resolution, Factum Arte built a non-contact colour scanning system that
uses a large format CCD and integrated LED lights. The scanning system records
at a scale of 1:1 at a maximum resolution of 1200 dpi. The scanning unit is
mounted onto a precision built telescopic mast, which is operated by an air-pump
and can accurately position the scanning unit on the vertical axis. It has a
maximum reach of 8 meters from the ground, is fitted with a linear guide to
position the scanning head in front of the painting, and has an ultra-sonic distance
sensor to ensure that the scanning head is a uniform distance from the painting
and is always positioned parallel to the picture surface. This is essential to ensure
that each file can be merged together without scale, focus or perspective
distortion. The scanning takes place at 8cm from the surface of the painting.
The scanning head moves over the surface illuminating the area that is
being recorded. LED light contains no ultraviolet rays and generates minimum
heat. The painting was scanned in 37 columns and 43 rows. Each capture was 22
x 30.5cm with an overlap 4cm on the horizontal dimension and 7cm on the
vertical dimension. Each file was saved in 2 formats (Tiff and Jpeg). The Tiff is
the working file and the Jpeg is a reference file. The recording was done at 600 dpi
with 16 bit depth of colour. During the recording of "Les Noces de Cana" 1,591
individual files were saved in Tiff format resulting in an archive of 400 gigabytes.
The telescopic mast was also used for conventional photography using a
Phase One H25 digital back fitted to a medium format Hasselblad body. The
Phase One records 5488x4145 pixels (22 megapixel) with a pixel size of 9x9
microns and 48 bit colour (16 bit per channel). The photography was done in 450
sections (18 columns and 25 rows) using the ambient light in the room. For
reference, a photograph of the complete painting was taken with the camera
positioned on a tripod in front of the Mona Lisa at the other end of the room
ensuring minimum distortion. The archive of photographic data consists of 593
different files totalling 41 gigabytes of data.
The lower part of the painting was recorded using a non-contact 3D
scanning system made by NUB 3D (Spain). No markers, spheres or registration
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systems are fixed to the object. The average working distance is about a meter
away from the surface being recorded. The NUB 3D Triple White Light Scanning
System uses a mix of optical technology, 3D topometry and digital image
processing to extract 3D coordinates from the surface of an object. This
technique, known as structured white light triangulation, produces accurate
measurements of the surface by analysing the deformation caused when lines and
patterns of light are projected onto the surface of an object. Multiple images are
captured by an integrated camera in the measuring head and using these images
the system's integrated technology calculates a co-ordinated X, Y, Z point cloud
relating to the surface of the object. About 10 sq meters of the painting were
recorded in 3D at a resolution of between 400 and 700 microns. The scanning
was done in sections of one meter square generating an archive of about 1
gigabyte. Due to the tonal difference of the surface and the varnish a multi-
exposure option was used. For the alignment and post processing Invometric
Polyworks software was used.
During the recording extensive colour notes were made using a series of
colour sticks made on site and matched to specific points on the surface of the
painting. These were fixed into a book containing a 1:1 scale line drawing of the
painting. A bit of the colour stick was cut off and fixed into the book at the
corresponding point on the painting.
The first task of assembling and aligning the data, carried out while
working in the Musée du Louvre was to pre-assemble all the columns using
Photoshop Scripting. This resulted in a roughly assembled image of the entire
painting. The final assembly, carried out in Madrid, was to reduce the 1,591
individual files into larger units accurately joined together. The vertical columns
were used as the basic unit and each scan was accurately assembled into strips
comprised of 8 or 9 scans. Each full column is made of 5 of these files. The file size
of each unit is about 1 gigabyte. 185 of these units make the whole painting (with
overlaps).
The edges of the painting were accurately assembled in order to give an
absolute reference. Three horizontal lines were established across the painting to
ensure no distortion was taking place. Four vertical lines were then stitched to
these horizontals and the resulting blocks were filled in the same way, sub-dividing
each one into horizontal and vertical areas. This avoided any compound
distortion and ensured an accurate master file. The master file was broken down
into manageable units (file size under 12 gigabytes) with an accurate reference to
each adjoining unit. Once these units were finalized the individual scans were
flattened. The painting was then divided into 1 x 2 meter blocks - these blocks are
the printing units. There are 44 printing units.
The scanner data and the colour photographic data have to be treated
independently but aligned in perfect registration. The photographic data
(recorded in 16 bit depth of colour per channel in RGB) has to be mapped onto
the basic scanner data unit of 1 x 2 meters. The scanner data contains no
distortion but the camera data always contains some lens and perspective
distortion. To join these two types of information, each photograph has to be
generally distorted and then locally transformed, using transparency in different
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blending modes depending on the nature of the data. This is mainly done using
features in the picture such as brush marks or 'noise' within the canvas.
When more than one data set is used, the usual difficulties of color printing
increase exponentially. The aim of the colour adjustments was to make Factum
Arte's flatbed printer match the colour sticks recorded in the Musée du Louvre.
The monitors were all calibrated to the colours that were being printed onto the
gesso coated canvas. The colour of the gesso is not a pure white so it was
important to create a range from the lightest white to the darkest black. The exact
matching of all the colours was then a question of trial and error involving
changes to both the digital files and the gesso mix. Printing began with the panel
at the bottom left of the painting and further changes were made until both the
tone and the colour of the two layers printed together matched the colour sticks
after the print had been varnished. Every change was archived and then simplified
gradually resulting in a series of Photoshop "actions". One set of actions was
applied to the Phase One data and another to the Cana Scanner data. Once
finalized, these actions were applied to all 44 printing files and small versions of
each file were printed. During the recording the lighting conditions for the
photography and the scanning were kept constant so these universal actions, in
theory, result in accurate colour matching across all parts of the 67 sq meter
canvas.
After printing the tests and comparing them with the colour sticks further
local corrections were made to specific colours that were not exact in terms of hue
and tone. This mainly applied to areas with a lot of whites or with complex greys
and blacks. These changes are made using locally applied masks to isolate specific
areas of the painting.
The facsimile was printed on Factum Arte´s purpose-built flatbed printer.
This is based on an Epson Pro 9600 digital printer. The printer uses pigment inks
in seven colours (cyan, light cyan, magenta, light magenta, yellow, black and light
black). The bed is fixed and the print heads move up and down the bed on linear
guides. The movement of the heads is accurate to a few microns. The height of
the heads can be adjusted during printing. This enables the image to be printed
onto gesso coated canvas in pigment. The gesso coating uses no metal oxides and
is a mixture of animal glue, calcium carbonate and precipitated chalk. The texture
on the surface of the 16 oz. Irish Flax is made from flax fibres and threads mixed
with the gesso. Acetate sheets are printed with the Phase One H25 data and used
for the positioning of all the texture onto the surface of the canvas. Due to its
history "Les Noces de Cana" has a complex and unusual surface. To reproduce
this appearance, each piece of canvas is coated with a layer of animal glue, a layer
of gesso and fibres and then two layers of gesso. The acetate sheets are then used
with a pin registration system to accurately locate the print on the prepared
canvas. Each panel is printed twice in perfect register. The first layer to be printed
is the information recorded on the Phase One H25. The second layer is the
scanner data. The overprinting results in accurate colour matching and a control
of the tonal values of the painting. The entire image was divided into printing files
of 110 x 220. Each file has 10 cm of overlap. The printed panels are varnished
with a satin Golden acrylic varnish with UVLS (an ultra-violet filter).
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Ten 20mm thick Alucore panels were made. Each panel is 340 x 205.2 cm.
When perfectly aligned in two rows of five panels they make up the whole
painting. Each of the large aluminium panels is assembled from 6 printed panels
with some of the panel overlapping the edges. First the printed panels are laid out
on the surface and perfectly aligned. They are then spliced together with irregular
cuts that follow features in the painting. Straight lines are always avoided. The
canvas is then fixed to the aluminium with PVA. The joins resulting from the
stitching of the printed panels are then retouched by hand by a team of trained
conservators. The joins are first filled with a mixture of Golden acrylic moulding
paste and glass microspheres. When the join has been carefully filled it is first
tinted and then retouched using Golden acrylic paint. During this process a gloss
Golden varnish is used. A Golden gel is then used for the final texture and to
enhance selected brushmarks and areas of impasto paint. A final coat of satin
Golden varnish with UVLS is applied.
The honeycomb aluminium panels, with the retouched printing, were sent
to Venice in sections and then fixed on site to an aluminium frame. This was done
in two parts which were then lifted into place and fitted onto the wall. The final
filling, retouching and control of the surface was done when the facsimile was in
its final position and with the lighting that exists in the refectory.
See: www.factum-arte.com
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