This Conveyor Belt Digitizes Museum Artifacts in Seconds

The Smithsonian built an assembly line for historical documents that can digitize roughly 3,500 things each day.

Kelli Korducki

The Smithsonian built a conveyor belt that can scan archival documents in seconds, rather than the 15 minutes it could take before. ​Photo: Brendan McCabe/Smithsonian

​When the Smithsonian decided in 2012 to make new digital scans of all of its stuff, museum staff knew they couldn't do it all by hand. So they bought a giant conveyor belt instead—one that can ingest new documents every few seconds, versus the 15 minutes it could take before.

While digital imaging is nothing new for libraries and museums—some archives have been digitizing documents for archival purposes and online access since the late 1990s—there's been increased demand to speed up the process, and to widen its scope to include 3D images of physical objects such as sculptures and vases. But when you're dealing with the glut of material the Smithsonian is, digitization poses a logistical challenge. By recent estimates, there are approximately 150 million objects in the museum's massive collection, totalling some 164,000 cubic feet of archival material (including paper documents, audio and video recordings, photographs and films) and over 1.8 million volumes of library documents.

Old bank notes ready to be scanned are placed on sheets. ​Photo: Brendan McCabe/Smithsonian

That's a lot of things to scan. And given the size of the Smithsonian's collection, creating images of the objects one-by-one would take over a century without stopping. No one's got that kind of time.

Instead, the museum's Digitization Office adopted a "rapid capture" digitization process—essentially, a conveyor belt with a camera overhead—enabling high resolution 2D images of roughly 3,500 materials to be created each day. Smithsonian staff launched the initiative with a series of glass plate negatives in August 2013, and are expected to complete their first collection this March: 250,000 proof sheets used for printing currency, war bonds, bank notes and other monetary documents from 1863 to 1930.

Compared to previous techniques, the Smithsonian's approach is tidal shift in the way museums worldwide are tackling the digital imaging process, and the first time such technology has been used in the US.

"The car was invented in like 1885 and people did a lot of good things between Henry Ford and the assembly line. But it really wasn't until the assembly line came around that mass production democratized access to the automobile," says Ken Rahaim, the Smithsonian's digitization program officer. "I kinda see a little bit of an analogy between what we're doing now with this industrialized approach to digitization, and assembly line manufacturing."

The conveyor belt was purchased from a third-party company and calibrated to fit the museum's specifications. It is similar to the conveyor belt we toss our shoes onto in airport security, but with markings on the belt to indicate precisely where museum workers should place objects awaiting to be scanned. A custom 80 megapixel camera system takes images of each document from above with a whopping resolution of a 690 pixels per inch—sharp enough to see "intricate designs of only twenty micron thickness," according to a separate post by National Museum of American History staff last year.

When the item at the end has been removed, the belt moves on. The images turn out more or less the same as ones scanned individually—but they're produced at a much, much faster rate.

But while the results are impressive, the reality is not everybody has access to the technology and financial resources of the Smithsonian, which boasts the distinction of being the largest museum and research complex in the world. Other institutions, such as the Canadian Museum of Nature in Ottawa, Ontario, and the Canadian Museum of History (CMH) in Gatineau, Quebec, still digitize objects individually by hand.

The CMH alone has scanned around 250,000 documents since the mid-2000s.

"Every museum has their own needs," says Kathleen Brosseau an information analyst within the museum's photographic archives and new media department. But after a decade of producing low-resolution JPEG scans of photographs and miscellaneous museum records, Brosseau found herself inundated with requests for higher resolution versions of the same items. She realized it made sense to establish concrete guidelines that would prevent people from having to re-scan items again in the future, and with Mylene Choquette and Louise Renaud, released a set of digitization standards for the Canadian Museum of Civilization in 2006.

Late last year, the museum joined the Bibliothèque et Archives nationales du Québec (BAnQ) and the Bibliothèque nationale de France (BnF) to produce a compendium of best practices for digitization in other museums across the Francophone sphere. These include recommendations to scan documents in greyscale or colour, rather than black and white, and to keep a border around the document to allow for later re-framing and other modifications.

Scanned documents are retrieved at the other end of the conveyor belt. Photo: Brendan McCabe/Smithsonian

But Renaud points out that, for museums large and small, image capture strategy is always subject to revision.

"The Canadian Museum of Civilization has been digitizing since the 1980s—maybe '70s," she says. "First, we had the old videodisk format. We had artifact photos taken and put on videodisk. Then after that format dropped, we started digitizing in the PCD Kodak format that became obsolete in 2000. We had maybe half a million of those images." Flexibility to adapt and keep up to date with the latest imaging formats is a key element of the archival process.

The potential for more museums and archives to speed up that process might make digitization a little more palatable. Rahaim estimates that his Digitization Office has rapid scanned some 250,000 to 300,000 objects, through a series of special projects, so far. These are in addition to the roughly 300,000 items digitized separately by the Smithsonian's 19 museums and nine research centres.

"It's an indication of efficiency of the process, and direction we need to go in," he says. Museums of the world are undoubtedly taking note. 

Correction: An earlier version of this story indicated that the Smithsonian built the conveyor belt itself. Rather, it was purchased from a third party company, and calibrated to fit the museum's needs. The story has been updated to reflect this.