A journey into learning a (3D!) restoration process workflow

WIP on a hair pin ornament

Introduction: the path to choose

You may have wondered how an object can go from being (re)discovered in a dusty attic or an archaeological site to a neat, well lit museum window display. And then how it can be seen in the institution website or a VR headset app. You are not alone. So did I.
Moreover, how can new technologies help us, cultural heritage professionals, to fulfil our missions of preserving pieces and showing them to the public.

I’ve decided to document this journey into finding out and trying it for myself in a series of articles. Spoiler alert, look at the title again, the digital side of things will be highly emphasized!

1 Analogue and digital: two ways of preserving pieces.

1.1 Digital opens up possibilities

1.1.1 New tools, same trade

The motivations behind this very act of retrieving a tangible piece from its natural timeline of creation, use and destruction is beyond the scope of this article. It has been and still is a constant subject of entrenched battles between scholars.
I’ll just brush the fact it is the result of a thorough scientific process that will henceforth dictate how and when a piece is subjected to any curation and conservation acts.

Until recently, say 50 to 30 odd years, the conservation side of the trade developed mainly as an extension of a traditional workshop. It uses the same tools, same know-hows and same actions though adapted to suit a different endeavour. Then, the methods and workflows changed, aided by scientific research and industrial production of new tools and chemicals. The shift revolved around the idea of not creating a sort of new piece, but more to restore an existing one. That is to say, to ensure it can still be understood while respecting the original material and making sure actions taken can be undone without damaging the artefact.

Within the last 15 years, technology has made other huge leaps in allowing the widespread diffusion of “new” tools and methods beforehand confined to specialized labs driven, again, by scientific research. Workshops everywhere evolved around these new helpers and can now use them to create new objects differently.

Conservation can dutifully follow suit and use these new developments for its own purposes.

WIP on a grotesque model based on a 19th century etching
WIP on a grotesque model based on a 19th century etching

1.1.2 New tools, new rules

View of a relief being created in a 3d app from a19th century etching reference
WIP of a relief created in a 3d app from a 19th century etching reference
Multiple views of a green man themed door ornament in a 3d app
WIP Creation of a digital double of a green man themed door ornament from a museum piece reference
Antique oil lamp being recreated and put in context in a 3d
WIP of an antique oil lamp bing created and contextualized from a museum piece reference

More than that, these new tools can be used to care for preserved pieces, so they can be shared with everyone on a way larger scale. As with all new things, it has needed and will need for workflow adaptations and new skills’ development, as well as a careful consideration of what is at stake both in terms of quality and durability.

Enters digital medium.

It has and is enabling institutions, galleries and collectors alike to showcase both the pieces and the context they were created in (try this example from the Smithsonian). It allows showing things differently, sometimes better, as in allowing a closer proximity, and to cater to more publics including creating tools for disabled audiences, whether full digital tools or 3D printed enhanced fac-simile for example. Furthermore, it can quite literally visually contextualize the piece according to the research state at that point in time and therefore mediate the pieces differently. And if and when research shows another point of view, it can be updated without any risks to the actual piece.

As a communication medium, digital content allows us to get rid of things like the geographic barriers, the limited showroom space and all the conservation issues linked to a direct presentation such as exposing very fragile pieces to too harsh a light in order to be seen correctly.

As far as conservation goes, a 3d reconstitution is also a way to try things out without damaging the tangible piece. Or access things that were almost impossible to come by before. For example, no elephants would be harmed in the digital restoration of a chryselephantine statue !

Don’t get me wrong, I’m perfectly aware data processing still has a cost, just like a regular workshop is not ecologically neutral.

For a more detailed development with illustrations, you can find 3D examples on this page.

WIP Textile reconstitution trials in a web viewer (13th century, Syria)
WIP Textile reconstitution trials in a 3D app
WIP Textile reconstruction hypothesis trials in a 3D app (12th century, Liao or Jin dynasty)

1.2 Integration into the traditional curation and conservation workflow

1.2.1 Initial steps = Common steps

Once an object enters the heritage status paradigm, it should theoretically be subjected to different operations. In reality, this process is iterative and can span on the lifetime of the institution itself.

First and foremost, inventory and registration take place. This is a very administrative and quite formal process. I didn’t say tedious. There are rules and protocols to follow. One of the steps taken is to assess the object material state by creating a condition report. This can be done by anyone involved. A registrar and a conservator won’t see the same things because they’re not driven by the same objectives.
Though it is always more informative to see a piece in real life, it is not uncommon to ask for a more specialized colleague’s advice by sending pictures to make an educated hypothesis. “See this crack there ? Was it voluntary ?”. See what I did there ? Photography has been a part of these first forays into the object’s secrets ever since decent pictures could be taken. Ideally, a full coverage is done with views from all sides and details.

Conservation choices are derived from this assessment with the added idea of curation objectives to pursue. They dictate the next steps to be taken (classification, preventive actions, curative actions or full restoration etc.). Don’t feel lost in the vocabulary, every field has its own. The FAQ page gives a few definitions that might help.

Parallel to these evaluations, the object is documented as best it could for the time being. It serves multiple purposes, including writing an accurate description and putting forward historical contextualization. This creates a frame to work with from the “birth” of the object, to the “life” it has gone through. The more is known, the better it is to understand the state it’s in and the need to do or not do something.

In a restoration process, whatever the kind, all these steps are needed because each of them gives useful information to select a process to follow and to drive the actions to put in place.

Researches, reference and colour palette creation while creating of a digitally restored 3D double of an owl shaped aryballos from a museum piece reference
WIP Researches, reference and colour palette creation while creating of a digitally restored 3D double of an owl shaped aryballos from a museum piece reference

1.2.2 My workshop has gone digital !

At that point in a traditional restoration process, one would probably grab a brush or an air blower and start dusting. This is the very first and mandatory act that needs to be done before anything else, no matter what YouTube showed you.
Seriously, people. Clean the objects first. This is non-negotiable.

In the process of creating a digital copy of the piece, there is also need for some cleaning up, whether from the scanner files or from the reference pictures. The former will probably need some retopologizing and texturing clean up. The latter are more of a comparison between the pictures and the description/ condition report to try and decipher what is and what isn’t.

At that point, of course, the two workflows part. I’m not sure if there is a definite digital method, just as there is absolutely no definite traditional one. Every workshop or studio have their own ways. More than that, it is quite certain, said ways change for every piece to adapt to the situation and complete the process.

Digital sculpture training from photo references
WIP Digital sculpture training from references

2. Keep moving forward

2.1 Training process for me

“ … Hâtez-vous lentement ; et, sans perdre courage, 
Vingt fois sur le métier remettez votre ouvrage :
 Polissez-le sans cesse et le repolissez ; 
Ajoutez quelquefois, et souvent effacez…”
Nicolas Boileau, L'Art poétique.

This is a quotation in French that roughly translates to “Hasten slowly, and without losing heart, put your work twenty times upon the anvil.” Though, it really doesn’t have all the strength the original saying has. It sums up what the digital restoration process is for me.
Coming from a more traditional curation and conservation background, this path is part of a journey of never ending learning process. All jobs are like that. This is mine.

wireframe view inside a 3d app
WIP Wireframe view of a Wardian bottle concept idea being developed from literary sources.

2.2 New tools, new rules, new skills ?

This is a whole new domain to explore. There are numerous basic skills to acquire before considering a project. They then need to be refined.
Digital processes are now more and more used in the heritage field. New ideas, concepts and pipelines come in, but the fundamentals are the same. We preserve so everyone can see and learn from the past.

As well, I’m not certain the end line of the digital restoration process is whenever code is involved. I feel that it then just changes form and becomes a partnership, with people having the technological knowledge to quite literally present the object on new media. We know how it should look and feel, they can make it happen.

If this idea is of interest to you, I’m trying to emulate that with the creation of an online viewer, like so. It is both a proof of concept and an everyday tool.

WIP Creation of a digitally restored 3D double of an ornate beaker from a museum's collection reference available in a web browser
WIP Creation of a digitally restored 3D double of an ornate beaker from a museum’s collection reference available in a web browser

2.3 Make mistakes and try again

WIP 3D rendering of a crystal cut wine glass from a photographic reference
WIP 3D rendering of a crystal cut wine glass from a photographic reference

New tools come with new rules and ask for new sets of skills to build upon my classical training, and that comes with mistakes and doubts.
I’m taking comfort in the fact that what I thought was going to be worlds apart from a workshop practice just isn’t. I was as surprised as you may be!
Once the basic digital skills are in place then with the right amount of research and preliminary work just like in a workshop, everything then flows. Don’t get me wrong, this is not a Disney movie: there are hiccups and dead ends and things “that’ll be sorted whenever I can”. Also feathers. Don’t get me started on them. Worse part is, I like feathers; they’re just so -sigh- to do.

Description of shell decorated handle
Creation of a handle digital double with conch decor

This series of articles are a way for me to show my work and my process so that it may hopefully help others with the same ideas and goals to find information. More precisely, the information I needed but couldn’t find or couldn’t understand easily.

Learn, grasp, show.

You can find all this in put in practice in the articles below:

The importance of FOSS

Cultural heritage is a common heritage, it cannot be tied to closed formats, excluding anyone from benefiting from it. Going FOSS is not even a question, it’s a necessity.
But it does not make things easier for an everyday practice and part of my workflow still is dependent on closed software programs, though I’m actively working on solutions.

Tools I use

I do rely heavily on the following applications:

  • Blender for everything 3D
  • Krita as a painting app
  • Gimp as an image manipulation software
  • Inkscape for everything vectorial
  • Git for versioning, though I use only the most basic functions
  • Darktable and Rawtherapee for digital photography developments and as labs

As mentioned, I also use Non-FOSS software like:

  • Obsidian, a markdown editor and notes organizer (I don’t know what I would do without it, or how I did without it all those years)
  • Pureref, for reference compilation
  • Atom (TT) and VisualStudioCode for coding
  • Substance painter for 3D painting (yes, this one hurts!), I’m also trying to use Armorpaint as a replacement, but it’s still a struggle for me.

I’m sure there are others, I’ll mention them in the articles as I go. Oh, and, my OS is Linux Mint.

If the FOSS infrastructure for art related items is of interest to you, might I suggest M.Revoy’s site? He has articles there where he goes in-depth into the nitty-gritty of using and parametrizing everything.

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