Criteria for Selecting a Capture Technique

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The following factors may be considered when choosing an object for digital reproduction:

  1. What intellectual value does the object or artifact have?
  2. What intrinsic, or artifactual, value does the object have?
  3. How unique or rare is the object?
  4. How importance is the object for research and use?
  5. How does the artifact relate to a specific topic or area of study?
  6. What are the physical characteristics of the object, including any unique or unusual details, shape, color, etc?
  7. What aspects of the original object should be retained or discarded in the digital reproduction?
  8. Will the digital reproduction have value over the long-term?
  9. Will the digital reproduction add to content resources?
  10. Who is the intended audience for the digital reproductions or the digital project?
  11. What are the legal restrictions on creating a digital reproduction of an object?
  12. Are there specific copyright restrictions?
  13. What are the costs involved in creating a digital reproduction and maintaining the digital reproduction long term?
Judging Condition and Value of Original
  • Use gloves when handling any photographs or negatives.
  • For negatives, the emulsion side should be placed on the bed of the scanner.
  • Occasionally, flat items may be difficult to remove from the scanner bed. A small suction cup can assist in lifting the item enough to capture it with fingers. Suction cups should not be used on the emulsion side of a negative or image.
  • Handle manuscripts, bound items and books with care, particularly fragile books that have damage to the spine, covers, or text block. Gloves may be used to avoid contact with disintegrating leather bindings.
  • Gloves may also need to be used for artifacts.
Handling Originals
  • Master images are meant to capture the original object and should mirror or duplicate it as exactly as possible. Derivatives made from the master scan may include changes or corrections in the appearance of the object for presentation purposes.
  • Always use the color bar when scanning color photographs. It is not necessary to use the color bar when scanning negatives or transparencies or when scanning an image in grayscale.
  • The color bar can be placed anywhere around the image. Capture enough of the color bar to distinguish the colors. The entire bar does not need to be included unless the measurements of an image or object need to be captured (e.g. for photographic captures).
  • The color bar should remain several millimeters away from the artifact, to facilitate easy removal of the bar in derivative images.
  • The color bar should be used when scanning objects of "high artifactual value" or importance. In these instances, best judgment may be used when considering the use of a color bar. Please note that the color bar does not need to be used with the Zeutschel overhead book scanner.
  • All images are scanned with RGB color. The exception to this includes black and white photographs that are "true" black and white in color, not those with a sepia or brown tone. These items may be scanned in grayscale.
  • All scans of transparent items should be completed in "transparency" mode in the scanning software.
  • The benchmarks used for creating digital scans and images are meant to comply with or exceed the recommendations of the "Digital Library Federation Benchmark for Faithful Digital Reproductions of Monographs and Serials."
  • Scanning benchmarks should adapt to the original item or type of media that is being scanned.
Recommendations for different types of objects are noted in the table below:
Type of Object
DLFB Minimum
Color Bar
Specifications

Manuscript text

600 dpi
1-bit or bitonal

Kodak
Color

600 dpi, 24-bit
Color

Printed text

600 dpi
1-bit or bitonal

Kodak
Color

300 dpi, 24-bit
Color

Printed text with graphics

300 dpi
8-bit grayscale

Kodak
Color

600 dpi, 24-bit
Color

Black White Photograph

300 dpi
8-bit grayscale

Kodak
Color or Grayscale

600 dpi, 24-bit
Color or Grayscale

Color Photograph

300 dpi
24-bit color

Kodak
Color

600 dpi, 24-bit
Color

Black White Photo Negative/Transparency

Equiv. 300 dpi
8-bit grayscale

N/A

Equiv.
1200 dpi, grayscale

Color Photo Negative/Transparency

Equiv. 300 dpi
24-bit color

N/A

Equiv.
1200 dpi, 24-bit color

Microforms

Equiv. 300 dpi
8-bit grayscale

N/A

Equiv. 600 dpi, 24-bit
grayscale

Maps

300 dpi
24-bit color

Kodak
Color

600 dpi, 24-bit
Color