Monday, February 18, 2013

George Washington Like You've Never Seen Him Before!

Though Conservation Fellow Josiah Wagener's project primarily involves the conservation treatment of painted folk art, he took some time out to help me out with the  photo documentation of one of my projects using a new-to-us technology. We're grateful to the Samuel H. Kress Foundation for funding Josiah's work here at Shelburne Museum. 

Here's Josiah:

How do you fully document a large counter relief object such as this early 19th century cake mold featuring General Washington?

The cake mold as photographed under normal conditions in the lab.

It has deep shadows, sharp corners, gentle curves, highlights, stains, cracks, grain color, and polishing from past use. How can you get all of that detail in to a simple photograph? Well, instead of a photograph how about an RTI?

RTI, short for Reflectance Transform Imaging, is a technique in which multiple photographs are taken of an object with the light coming from a different direction in each picture. The several photographs are then fed into a special computer program that combines them, reads the surface texture of the object, and creates a composite image with almost 3-dimensional feel.

31 images were assembled to create this RTI
Once the image has been created one can use the viewer program to virtually pan a light across the surface of the digital object, just as one might tilt and rotate an actual object under a light to get the best view of the highlights and details. Here's a screen capture of what its like to look at the RTI using the viewer program:

The RTI documents all the details of the object for posterity.

Although the technology has been available for a few years it is just beginning to see popular use and has never been used here at Shelburne before. Thanks to the work of the folks at Cultural Heritage Imaging, the RTI tools and technique have become much more easily available to anyone who wants to use this powerful technology. I recently taught myself the technique and assembled the necessary (very basic) equipment, and with the help of conservation intern Rosella Fevola,  we successfully created an RTI image of the Washington cake mold on our first attempt.

We intend to keep experimenting with the opportunities and limitations of this technology and find new ways to fit it into our conservation process here at Shelburne.

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