Global Gateway | Selections of Arabic, Persian, and Ottoman Calligraphy >> Building the Digital Collection
Eleven years ago the Library of Congress photographed its entire collection of calligraphy sheets on large format 4x5-inch color slides. Before the start of this project, tests were conducted both on the color slides and the original calligraphy sheets to determine which would produce the truest color representation of the calligraphy sheets. Staff from the Library’s Conservation Division and the Digital Scan Center, as well as the project curator, analyzed the scans of the 4x5 color slides and the calligraphy sheets side by side and determined that the original calligraphy sheets should be digitized.
Due to the delicate nature of the calligraphy sheets, the Digital Scan Center, in a unique approach, set up a PhaseOne P-25 camera in the African and Middle Eastern Division. This camera allows instant captures of the calligraphy sheets, thus reducing the amount of time that the calligraphy sheets are exposed to light and other wear and tear involved with conventional scanning. The few large-format calligraphy sheets were digitized in the Digital Scan Center using a TTI ReFlex 45ei with a PhaseOne scanback. Master, or archival, versions of the manuscripts were produced as 300-dots-per-inch (dpi) color images in the TIFF format, as well as high-quality and lower-quality JPEG images and thumbnail GIFs.