Chapman and Kenney, Digital Conversion of Research Library Materials, D-Lib Magazine (October 1996)

Example 2. Full informational capture of text and halftone

300 dpi 1-bit, with halftone descreened

- 1.4mm text in caption captured with legibility only

- halftone descreened, but undersampling results in graininess, especially evident in the printed version

does not meet criteria for full-informational capture

*note: image at left is a 100 dpi 4-bit GIF derivative; to evaluate quality of the 300 dpi 1-bit version, see the PostScript example (below)


600 dpi 1-bit, with halftone descreened

- 1.4 mm text in caption captured with fidelity

- halftone descreened; detail and tones represented w/o moiré

satisfies criteria for full-informational capture

*note: image at left is a 100 dpi 4-bit GIF derivative; to evaluate quality of the 600 dpi 1-bit version, see the PostScript example (below)



600 dpi 1-bit, no enhancements for halftone

- 1.4 mm text in caption captured with fidelity

- full tonal range of halftone not represented

does not meet criteria for full-informational capture

*note: image at left is a 100 dpi 4-bit GIF derivative; to evaluate quality of the 600 dpi 1-bit version, see the PostScript example (below)

source: Andrew Boss, Farm Management, Chicago, New York: Lyons & Carnahan, 1914, p. 136.

To evaluate and compare quality of TIFF images (the archival masters), download and print:

Postscript version: EXAMPLE2.PS [1,044Kb]

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