Cultural Heritage Imaging

4-Day RTI Training at the Metropolitan Museum of Art by marlinlum
January 5, 2011, 7:37 pm
Filed under: Commentary, Training
The Met

Metropolitan Museum of Art

In mid-December, we braved the cold and headed to the Big Apple for a 4-day RTI Training session at the Metropolitan Museum of Art, to be followed by a day of consulting on special projects. We were all delighted to be there and to enjoy the magic of Christmas-time in New York!  And of course, it was a true privilege to be welcomed by the Met. Thanks to Larry Becker of the Objects Conservation Department for inviting us, and thanks to Carolyn Riccardelli and Ashira Loike for making all the arrangements and plans.

Larry Becker and the OCD (includes CHI)

Day 01

We began our Monday with introductory RTI lectures and our favorite fish fossil demo for an audience of nearly 50 museum employees! After lunch, a core group of 16 Met staff joined us for a hands-on RTI shoot. It was interesting to hear about each participant’s interest in RTI – examining armature marks on a bronze sculpture, looking at scratches on copper plates, searching for fugitive paint on a wooden object, and other great research questions. For the afternoon RTI shoot, an Islamic writing box was selected. The goal was to establish a condition image, with close-ups to examine construction details and to try to determine if the white inlay displays characteristics of bone or ivory.

Day 02

The following morning, we processed the writing box data set, creating an RTI.  An interesting observation: we need an RTI databank, so that we know what ivory and bone are “supposed” to look like in an RTI image. In the afternoon, we headed to the objects conservation department and divided into two RTI capture groups and one processing group. Despite some technical glitches with the Met’s Nikon camera and new computer, a number of successful RTIs were created, from an enameled plaque to an engraved lead ingot.  By the end of the day, the conservators seemed encouraged that they could really do this — and, Anna Serotta and Ashira managed to get the Nikon and computer up and running.

Day 03

One of Wednesday’s highlights was a lecture by CHI partner Dr. Szymon Rusinkiewicz of Princeton University. The audience seemed particularly interested in Szymon’s description of using computational photography to help mend a severely fragmented fresco. Szymon also discussed some of his ongoing collaborative work with CHI, including the research and development of algorithmic rendering using RTI capture data.

Most of the rest of Wednesday was a three-ring circus (in a good way) – three RTI capture stations were established, and conservators busily shot image after image. The intention was to provide practice with large and/or upright objects. Everyone seemed to be focused and engaged in the process. It was empowering to see Met staff taking over after only a few days of instruction. RTI = Reflection Transformation Imaging = Real Teamwork Involved!

Day 04

Thursday’s morning lecture covered post-processing issues, using highlight maps to show the actual light positions that were captured. The class considered different and better ways to gain even higher quality results. Then, RTI capture and processing moved back to the Objects Conservation Department.  A bronze Bodhisattva, an African mask, and a historic violin were imaged – the conservators are still pondering the results.

Carla teaching

Processing and viewing RTI files are easy, but it takes a good amount of concentration. Carla in teaching mode.

The class ended with a “show & tell”, and we got to see each other’s results! Our immediate feedback is that the conservators really took to the new technology and that they enjoyed working together as a team. From CHI’s perspective, we were gratified, pleased, happy, and exhausted!

Day 05 – Day of Consulting

The CHI team did return to the Met on Friday for a day of special consulting. Mark Mudge and Marlin Lum worked with Anna, Carolyn, and Ashira to document a relief in the Tomb of Perneb. Mark helped Debbie Schorsch and Daniel Hansdorf with a microscopy set up to shoot an RTI of a metal fragment – they were delighted to see toolmaker’s punch marks! Meanwhile, Carla Schroer used her software expertise to concentrate on RTI post-processing and viewing support.

After an eventful and productive week at the Met, the CHI team returned to California feeling like we’d not only worked with new colleagues, but made new friends.

By Elizabeth Peña and Marlin Lum