It was pretty exciting to read Brandon Olson, Ryan A. Placchetti, Jamie Quartermaine, and Ann E. Killebrew, “The Tel Akko Total Archaeology Project (Akko, Israel): Assessing the suitability of multi scale 3D field recording in archaeology,” in the Journal of Field Archaeology 38 (2013), 244-262. Brandon is our field director at the Pyla-Koutsopetria Archaeological Project and my former M.A. student at the University of North Dakota. He’s finishing his Ph.D. in Archaeology at Boston University.
The article documents the use of Agisoft Photoscan at the site of Tel Akko in Israel, where a team lead by Ann Killebrew. Agisoft Photoscan (or as we called it The Agee-softs) is software that uses photogrammetry to create 3d images. I’ve posted on how we have used this software before on this blog. The article provides thorough instruction on how to use this software to produce accurate three-dimensional models of everything from cylinder seals to entire landscapes. Taking photographs for photogrammetry is deceptively difficult, and Olson et al. provide some nice illustrations and descriptions of best practices.
Moreover, the address various technical aspects of the practice ranging from the computer power necessary to process these images as 3D models to archiving methods to ensure that these models can be reproduced in the future. The article also demonstrated the remarkable accuracy of these this new software. It produced images with sub-centimeter accuracy making them practical rivals of much more expensive processes involving laser scanning equipment.
The practical tone to the article leaves open a few other conversations about the use of three-dimensional imaging software in archaeology. First, the historian in my looks to the past and considers the place of this kind of software and processes in the history of archaeological imaging. Since the advent of archaeological photography, archaeologists have sought ways to document excavation in a more efficient and technically precise way. The use of these tools, however, have transformed the way that archaeological knowledge is produced and reproduced. The precision and accuracy of 3D photogrammetry has the potential to transform how we understand archaeological data collection by allowing such interpretative acts as illustration to take place many month later and at significant physical remove. While such delayed illustration will probably never become “best practice” (there is real value to trench side interpretative drawing), increasingly high resolution reconstructions of the trench, architecture, and even entire landscapes strive to make more clear the lines between documentary and interpretative practices.
Equally as significant, if more practical, is the issues of disseminating 3D images. At present this infrastructure is woefully underdeveloped. Services like p3d.in provide relatively easy spaces to display and store 3D images, but these are hardly long-term archival solutions. Adobe has produced a 3D .pdf format (which I think relies upon the open standard U3D format), but PDF itself remains proprietary, it will be problematic. There are myriad alternative like PLY or the open-source COLLADA format that may hold the potential for not only more streamlined dissemination of 3D images, but also long-term archives of the results. It will be important to preserve some evidence for how the processing of 3D images relates to various interpretative results.
I have this idea for asking practitioners of various 3D imaging techniques to provide short thoughts on not only how they use such applications, but how these relate to earlier formats of archaeological imaging (from the sublime to the mundane) and how these formats will transform archaeology in the future. Would anyone who use these technologies in the Mediterranean want to chime in and send along short posts (<1500) to me for a series of blog posts? If it is as amazing as it could be, we could look to publish these posts in a short “best practices and future directions” booklet. Just a thought…
UPDATE: There was a great response to this post. So stay tuned for some blog based scholarship and maybe a quick open access book(-letish thing) in the early winter! And check out some 3D models from my site here.