digitization process
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The Digitization process

Every image presented on this web site has been captured on a PowerPhase One digital camera scanning back on a 4x5 ZBE Satellite copy stand at approximately 560 dpi, in 36-bit color. The high bit images are brought into Photoshop at 16B/channel (~210MB uncompressed .TIF files) and are color corrected within the Adobe 1998 RGB color working space. After making slight levels, curve and hue saturation adjustments the files are downsampled to 24 bit color (~105MB file size). For accurate color correcting the original print is placed in a 5000 degrees Kelvin Macbeth viewer, and compared to the image file as it is viewed in Photoshop on a hardware calibrated monitor which is placed to minimize glare in a low light environment. The monitor is set to a gamma of 2.2 and a 6500 degrees Kelvin white point. A cropped, color-corrected image was then made from this rich master file and used to create the .JPG files used throughout this site.

Images are presented on this site as .JPGs, in both 570 and 1024 pixels in width, for easy viewing over the internet.


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Fortifications on the Heights of Centreville Virginia, March, 1862 Photographed by George Barnard & James Gibson.

Cornell University

Division of Rare and Manuscript Collections

Copyright 2002 Division of Rare & Manuscript Collections
2B Carl A. Kroch Library, Cornell University, Ithaca, NY, 14853
Phone Number: (607) 255-3530. Fax Number: (607) 255-9524

For reference questions, send mail to: rareref@cornell.edu
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