Digitizing the Garibaldi Panorama
Digitization Overview
Photo: B. Tyler
Measuring ~4.75' tall and ~260' wide on each side, the sheer dimensions of the Garibaldi panorama presented unique digitization challenges. Boston Photo was contracted to capture digital images of the panorama as it was unrolled across a custom-built wooden platform. Using a vertically mounted Better Light 4" x 5" digital scan back, capturing both sides of the panorama took three days and resulted in 91 digital image files, each file ~244 MB and representing ~6.5' of horizontal width (including on average .5-1' of overlap, in order to facilitate subsequent image merging). The scan back captured 300 dpi RGB TIF files; given the height of the device this resulted in an effective real-world resolution of ~137 dpi at the actual size of the panorama.
Because scenes within the panorama’s visual narrative do not correspond to the uniform width used in the capture process, sets of capture files were digitally merged together five at a time, at full capture resolution within Photoshop CS3/v10, and then individual scenes were isolated and saved from these roughly 30-feet merged sections. A continuous image of each side of the panorama was produced by subsequently merging sequences of these five-section composites at a reduced resolution. As part of this process the plastic-over-board background initially visible along the top and bottom edges was digitally removed, and each merged group of five was slightly rotated in order to compensate for some inevitable alignment drift produced during the unrolling process. Tonal levels and saturation values were slightly adjusted, and files were moderately sharpened for full-resolution and reduced-resolution delivery sizes.
Preservation Concerns During the Capture Process
Photo: E. Saladino
As a result of the panorama’s past use, there are many tears in the paper, particularly at the top and bottom edges (as viewed) and at the leading edge of the giant scroll. There is evidence of many past repairs, from delicate Japanese paper repairs to heavier paper repairs painted to match the original watercolors, as well as pressure sensitive document repair tape and a great deal of hand-stitching along the leading edge. The top and bottom edges were once lined with canvas, but it is now missing on the bottom and only partially attached along the top edge.
The images consist of watercolors on paper — particularly fragile and susceptible to oils from human skin, not to mention damage from rough handling and exposure to light. The pigment layers are similar to gouache, opaque and thick, sitting on the surface of the paper and vulnerable to smudging as a result of abrasion, or to flaking as the paper substrate is flexed.
Preservation Department staff members reviewed the digital capture equipment configuration and discussed the process with the technicians, and determined that the best way to ensure safe handling of the panorama was to personally unroll and re-roll it as images were captured. The large dimensions and fragile nature of the nearly 150-year-old object required skilled, gentle, and experienced hands.
The panorama was unrolled across a wooden platform specifically constructed for this project; the platform was covered in plastic sheeting to provide a clean, smooth surface across which the panorama could glide. The plastic also minimized the likelihood of frayed edges and small tears snagging on the wood. Cotton gloves were required for anyone handling the panorama directly, reducing the amount of dirt and oil transferred to the paper.
Long-term Preservation Needs
The panorama came to Brown wrapped in a wool blanket and tied with ropes. The drums around which it is rolled are made of wood and board wrapped in heavy paper — sources of acid and other volatile organic compounds that lead to the deterioration of paper and pigments. To improve the panorama’s storage conditions, the paper was removed from the drums and replaced with thicker acid-free, lignin-free paper adhered with polyvinyl acetate adhesive and acid-free double-sided tape. The panorama was rolled as carefully as possible to minimize cockling or folds and wrapped with a layer of acid-free tissue and then with sheets of the same heavy paper now lining the drum to minimize any exposure to light. These sheets were secured with several paper belts.
Photo: E. Saladino
The paper itself is of good quality and is in good shape throughout most of the panorama, except in specific areas. These include a section along one edge with an unidentified stain that is very brittle and flaking apart, and both ends of the scroll, which are especially worn and have some large tears. These would need to be repaired if the panorama were to be handled or displayed on a more regular basis. Our current working assumption is that the availability of a digital surrogate will decrease the demand for in-person viewing to the point where the safe storage of the panorama in our climate-controlled Library Collections Annex is adequate protection and will preserve this object well into the future.