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This paper introduces the Watermark Imaging System (WImSy) which can be used to photograph, document, and study sheets of paper. The WImSy provides surface images, raking light images, and transmitted light images of the paper, all in perfect alignment. We develop algorithms that exploit this alignment by combining several images together in a process that mimics both the “surface image removal” technique and the method of “high dynamic range” photographs. An improved optimization criterion and an automatic parameter selection procedure streamline the process and make it practical for art historians and conservators to extract the relevant information to study watermarks. The effectiveness of the method is demonstrated in several experiments on images taken with the WImSy at the Metropolitan Museum of Art in New York and at the Getty Museum in Los Angeles, and the results are compared with manually optimized images.

American ethnomusicologist Andrew Toth spent decades in Bali, studying and documenting music of various styles. One of his most ambitious projects was to measure the precise tunings of every key and gong-chime of 49 gamelan gong kebyar, a popular form of bronze gamelan. However, his death in 2005 at the age of 57 prevented him from publishing a comprehensive analysis of his research. His tuning measurements included representative samples of gamelan from across the island, a treasury of data gathered as part of his multi-decade research with gamelan makers, tuners, and musicians. Seven boxes of his letters, photographs, concert notices, course notes, and computer printouts of tuning frequencies are now stored in the Special Collections & Archives of the Wesleyan University Library. This paper presents a first analysis of this tuning data, which comprises more than 8000 individual frequency measurements (approximately 150 for each of the 49 gamelan, plus five more sets of tuning data we commissioned). We utilize a unique way of visually representing the information, developed by Toth, that displays both the individual intervals of the musical scale as well as the distinctive tunings of the octaves of each scale degree. We call these Toth Plots, and describe in detail how the plots are drawn, now using modern computer graphics, and the kinds of information they help visualize. We have made the raw tuning data available by transcribing it into spreadsheets (machine and human readable), and will post the data in a publicly available location to encourage others to explore it. Based on Toth’s writings and data, we interpret several key tuning concepts relating to regional styles, interval models (such as begbeg-tirus) and octave treatment strategies. We also analyze geographic variations in the tuning measurements, which were taken in seven of the eight regencies of Bali at the time, and trace the evolution of the tuning of five of the gamelan from the 1970s to the present.