Tag Archives: 3D scanning

Thinking digital archaeology

This post is prompted by a recent (and freely available) article in the Journal of Field Archaeology, “Excavation is Destruction Digitization: Advances in Archaeological Practice” by Chris Roosevelt, Peter Cobb, Emanual Moss. Brandon Olson, and Sinan Ünlüsoy. Let me begin by saying that the article is really great. What the project is doing is innovative, cutting-edge, and thoughtful. But like Bill Caraher, I worry about some of the implications of the article, a couple of issues that caused me to frown and think.

Data and interpretation

The authors of the article make the important point that archaeological data are produced by decisions (and interpretations) made by archaeologists in the field, such that full digital documentation is not of the pristine archaeological record but rather of the excavators’ interactions with that record. Yet this point, once made, is not repeated, and the authors focus on improvements to accuracy and efficiency — for good reason, and persuasively so. Accuracy and efficiency are excellent goals, but once achieved, so what?

The proof of the pudding is in the eating. And in archaeology, what we want (I think, but I’m pretty jetlagged right now) are better understandings of the ancient world. And it seems to me that the authors haven’t made a particularly cogent argument connecting their methods and this ultimate goal. To be fair to them, this is not the main point of their article, but they do address the issue. First, we are told,

…we are, in effect, increasing efficiency and thereby providing greater opportunity for in-the-field reflection about depositional and post-depositional processes and the human behavioral and natural conditions that drive them.

Second, we are told that

Data sharing allows for the sort of broadbrush,inter-site comparisons that can increase understanding of some of the greatest concerns of humanity more so than can single datasets: climate change, social inequality, and urbanism, for example. If archaeologists argue that their work provides such public benefits, they must be willing to provide full access to their complete and original data as well as to their analytical results (Gestrich 2011). A significant goal for archaeology, then, is the free and open accessibility of such datasets. The most efficient way to reach this goal is to generate publishable or near-publishable quality data at the time and place of collection, so that additional data preparation—sure to slow publication—becomes unnecessary.

So, more efficiency is good because it means more time to think, and more (digital, standardized) data are good because they promote most efficiently large-scale comparison and querying. With regard to the first claim, when has increased efficiency in data collection ever yielded more time for contemplation? In my experience, it tends to produce the opposite: a stronger push to collect more. That’s been my experience working on my own digitization project, at any rate: I interact with the digitization and data capture, counting on the fact that the data I produce will bail me out down the line when I need to get to analysis. I’m somewhat less skeptical of the second claim, but it relies on the promise of future gains of comparison between field projects that, even if they use the same systems, are fundamentally dissimilar in all other kinds of ways. After all, as the authors point out in the first page of the article, digitization doesn’t actually record some archaeological truth, but rather the archaeological process of discovery. So publishing raw data, while laudable, doesn’t help us to understand urbanism (say) without an intimate knowledge of the archaeological processes that produced those data.

In sum, then, I suggest that while gains in efficiency and accuracy are great, it remains to be demonstrated that they get us something important. For instance, the authors present us with the example of a granary and their documentation of their excavation of it. It is impressive. But does it help us interpret the granary any better? It hasn’t seemed to thus far.

Skilling and deskilling

Another objection (or potential objection) that the authors confront is de-skilling:

others might fret that such developments are potentially ‘‘de-skilling’’ (W. R. Caraher, personal communication 2014), or at least that they diminish the reflexive value of mechanical or analog archaeological methods. On the contrary, we argue that skills are not lost, but only shifted from analog to digital.

Part of the problem here is that deskilling has a more specific meaning than loss of (some) skills. As Wikipedia, the font of all truth, helpfully informs us,

Deskilling is the process by which skilled labor within an industry or economy is eliminated by the introduction of technologies operated by semiskilled or unskilled workers. This results in cost savings due to lower investment in human capital, and reduces barriers to entry, weakening the bargaining power of the human capital.

It seems to me that this meaning of deskilling is what is at stake, and the argument therefore misunderstands the perceived objection. And this brings us back to my core concern about archaeological interpretation. Does this shift away from analog to digital skills help us as archaeologists to understand the ancient past? A deskilling argument would suggest that in this shift, we lose quality and skill in favor of efficiency. Think, for instance, of handmade goods made by craftsmen (e.g., a fine wooden rocking chair handmade by Ron Swanson) as compared to their modern counterparts made by unskilled and cheap factory workers.

Maybe? Probably? Probably maybe? I’m not sure. I do know that I’d prefer a rocking chair handmade by a craftsman than an efficiently-made, super-standardized rocking chair made in a factory. And I’d prefer a site excavated expertly and documented with paper notebooks than a site excavated reasonably well but with full digital documentation.

I suppose one could argue that this doesn’t mean that we shouldn’t digitize, because we can still innovate and improve. I agree. Yet it seems to me that what archaeological projects really need is lots of expertise at the edge of discovery. The Kaymakçı Archaeological Project (KAP), on which the authors work, clearly has that. But that expertise, in my view, will be much more decisive in their analytical success than their digital methods. And if this is true (or even partly true), then much more decisive for the field than the development of new digital methods will be the training of good archaeologists.

Our AIA talk on the digital imaging of Linear B

RTI with Jami Baxley

RTI with Jami Baxley

Kevin Pluta and I submitted an abstract to present a 20-minute paper at the upcoming annual meeting of the Archaeological Institute of America in Chicago (January 2-5, 2013) and we’ve just been notified that it’s been accepted. Here’s the abstract we submitted:

Digital imaging of the Linear B tablets from the “Palace of Nestor”

This paper presents a new project, whose goal is to create a print and digital edition of the administrative texts from the “Palace of Nestor” using advanced imaging techniques. Initiated in the summer of 2013, it is part of the official publication of the “Palace of Nestor” at Pylos excavated by the University of Cincinnati under the auspices of the American School of Classical Studies at Athens. We argue that digital editions such as ours have the potential to transform the study of the Aegean Bronze Age by allowing researchers to interact with artifacts at a level of detail and verisimilitude that approaches that of autopsy.

We employ two imaging techniques. The first of these is Reflectance Transformation Imaging (RTI), a method that involves taking multiple photographs of the same artifact under variable lighting conditions. These photographs are stitched together into an image file that stores the color of each pixel in addition to how it reacts to light, allowing the user to re-light the artifact in an interactive virtual environment. RTI therefore affords the opportunity to select the best lighting angle or angles for clearest presentation of the inscriptions. Our second imaging technique is structured light three-dimensional scanning, which has the ability to record accurate, low-interference surface data with minimal clean up. The technique is particularly useful as it collects color data that permit realistic renditions of the artifacts being recorded. In combination, these two techniques will provide the user with highly accurate renditions of the color, shape, topography, and texture of each and every administrative document from Pylos.

There are two closely-related advantages that we see to this digital imaging. First, we anticipate an improvement in the conservation and archiving of the physical artifacts, since the availability of high-resolution images in two and three dimensions will reduce the need for their study and handling. Second, a digital edition provides users with the ability to work interactively with the administrative documents in a digital environment. The resolution of the imaging is such that it even permits users to propose new readings and joins. This allocation of high-quality primary data to scholarly experts represents an exciting development. Far from being merely an enhancement of standard methods of illustration, these imaging techniques have the potential to transform the field by distributing control of the primary data to all qualified experts.

Also accepted was a submission for a poster, entitled “The use of structured light scanning for the study of the Linear B deposits from Pylos, Messenia, Greece,” and co-authored by the 2013 team: Ben Rennison, Jami Baxley, James Newhard, Kevin Pluta, and myself.

Reblog: Advanced imaging of the Linear B tablets from Pylos

This summer I co-directed (with Kevin Pluta) a project in which we began advanced imaging (RTI and 3D scanning) of the Linear B tablets from the “Palace of Nestor” at Pylos (modern Ano Englianos). These tablets are now housed in the National Archaeological Museum in Athens.  I’ve written a couple of blog posts elsewhere about the project: one for the website of the American School of Classical Studies at Athens (ASCSA), through which we applied for our permit, and another for the Archaeological Computing Research Group (ACRG) at the University of Southampton, a member of whom, Hembo Pagi, trained us in RTI. The posts say the same thing, more or less, to slightly different audiences. You can read the stories here (ASCSA) and here (ACRG).

3D scanning with Jim Newhard and Ben Rennison

3D scanning with Jim Newhard and Ben Rennison

IMG_0657

RTI with Dimitri Nakassis

IMG_0696

RTI with Jami Baxley

IMG_0444

RTI with Kevin Pluta (left) and Hembo Pagi (right)