Courtesy University of California, San Diego
Armed with thermal scans, LIDAR imaging, architectural diagrams, and 36 years of accumulated research, Maurizio Seracini is spearheading a new effort to pinpoint the lost masterpiece. He'll have a tight deadline of only seven days, and his team will burn the candle at both ends to make sure everything is in place so that they don't lose a minute.
Samantha Stout, graduate student in materials science and engineering, will be working on the scaffold in a materials lab designed to conduct on-site analysis using portable equipment. She is working with the rest of the team to plan the analytical survey and the instruments that will be used.
The surface of the original wall will first be studied using portable fiber optic Raman spectroscopy, which is a technique used to study organic material. This will be able to detect the presence of organic binders, glue, wax, pitch, calcite, or gesso on the surface of the wall in-situ before sampling.
After samples have been taken from the original wall, Stout will use stereomicroscopy in the on-site materials lab to visualize the sample and record digital photomicrographs. The sample will then be studied with x-ray fluoresence spectrometry, which is a technique that can detect inorganic elemental composition and thus the evidence of any pigments in the sample. The samples will then be taken to our off-site (off-scaffold) lab for further analysis, including reflected light and UV fluorescence microscopy, Fourier transform infrared spectroscopy (FTIR), embedding in resin for scanning electron microscopy (SEM) with energy dispersive x-ray analysis (EDS).
UV fluorescence microscopy can be used to visualize the organic material present in the sample. FTIR spectroscopy will be used to characterize the chemical composition of the organic material present in the sample (oils, binder, glue, wax). SEM will be used to visualize the microstructure of the sample, and the EDS will identify the chemical composition of points or micro areas within the sample. Through the use of these techniques we expect to be able to confirm the nature of the materials present on the original wall and determine if they are consistent with the mural painted by Leonardo.
David Vanoni, graduate student in CSE, has developed an Android tablet application that uses augmented reality to overlay multispectral imagery onto Vasari’s fresco. This app is being used as a positioning tool—it has helped us identify the areas of the fresco where we conducted additional radar scanning to help pinpoint the areas that we want to study; and it will help us align our drill locations. Using the various multispectral images that we have available, the app will also be useful for visualizing this data in real time on the actual fresco: You can point the app at the fresco, and select (for example) a thermal image, which will overlay the areas of cracks or voids and show where they are in relation to the painting. The app also has a wipe-off technology so that you look at the various spectral images (UV fluorescence, thermal, infrared, etc) by pointing the tablet at a painting and wiping off the areas of interest with your fingers.
Vid Petrovic, graduate student in CSE, is working on visualizing and integrating all of the data we have to help make the decisions we need to make on where to drill and how to maximize out chances of finding the Battle of Anghiari. He’s been working on bringing together all the different kinds of data: visible, LIDAR, and radar, as well as models of the scaffold, etc., and placing them in a virtual environment so we can see how it all comes together. He has been interpreting the radar data we have collected to understand what it means and what we can do with it—it has gotten people interested in the project but we can also use it to help us figure out where to drill and maximize our chances of finding the painting. Radar analysis has culminated in getting high-resolution radar scans completed and aligning the new radar data with our ground truth (LIDAR data) and making use of it in our decision process so that we have position accuracy.
Daniel Johnson, Calit2 associate development engineer, and Tom Wypych, graduate student in CSE, designed and manufactured the incision instrument, sampling tools, and associated methods and protocols for the sample extraction operation. The team also developed software to provide data analysis and precisely control the motion of the incision device as well as provisioning communications and data collection services during the on-site work in the Hall of the 500.
Protecting the Vasari
Restorers find existing gaps in the Vasari mural that can be used to search for "The Battle of Anghiari."
Behind the Science
The team gathers visible, LIDAR, and radar data and now must place them in a virtual environment.
Incision instruments, sampling tools, and methods for the sample extraction were designed for this project.
Il Leonardo Perduto
Tra scienza e alta tecnologia, le immagini che raccontano momento per momento la ricerca de la Battaglia di Anghiari.
Breve intervista a Dave Yoder, autore delle immagini
Il capolavoro di Leonardo è nascosto dietro l'affresco del Vasari nel Salone dei Cinquecento a Firenze?
Dietro le quinte della trentennale ricerca della "Battaglia di Anghiari"