The document provides guidance on best practices for digital imaging of collections for digitization projects. It covers recommendations for scanning different types of materials like text, photographs, maps and graphics. It addresses file formats, resolutions and dimensions for master, access and thumbnail files. The document also discusses metadata, storage, quality control and planning for future technology changes. The overall goals are to digitize at an appropriate quality level to avoid rehandling originals and create master files that can meet current and future user needs.

1. DIGITAL IMAGING BEST PRACTICES
Version 2.0 • June 2008
Bibliographic Center for Research
Collaborative Digitization Program

2. Digital Imaging Best Practices
OVERVIEW
Digital Imaging Best Practices:

offer guidance

 to provide digital imaging recommendations for institutions and
collections that are planning / involved in digitization projects.
It is a guide, not de facto standard, for digital imaging,

image capture, presentation, storage and preservation.
Source: Bibliographic Center for Research Collaborative Digitization Program
http://www.bcr.org/cdp/best/digital-imaging-bp.pdf

3. Digital Imaging Best Practices
SCOPE:
WHAT IS ADDRESSED IN CDP DOCUMENT
Digitizing and file format recommendations for:

 Text, photographs, maps, graphic materials, artwork and 3-D
objects, film and born-digital files
Suggested hardware configurations

Software considerations

Quality control

File naming conventions

Scanner and monitor calibration

Targets and color bars

Storing images


4. Digital Imaging Best Practices
SCOPE
What is not addressed in CDP document:

Scanning and file format recommendations for:

 Audio, video/moving images
 Project management
 Selection of collections for digitization

5. Digital Imaging Best Practices
PHOTOGRAPHS
Master Access Thumbnail
File Format TIFF JPEG JPEG
Bit Depth 16 bit grayscale 8 bit grayscale 8 bit grayscale
48 bit color 24 bit color 24 bit color
Spatial 400 to 800 ppi 150 to 200ppi 144ppi
Resolution
Spatial 4000 to 8000 600 pixels 150 to 200
Dimensions pixels across the across the long pixels across the
long dimension, dimension long dimension
depending on
size of original,
excluding
mounts and
borders

6. Digital Imaging Best Practices
TEXT
Master Access Thumbnail
File Format TIFF JPEG JPEG
Bit Depth 1 bit bitonal 8 bit grayscale 8 bit grayscale
8 to16 bit 24 bit color 24 bit color
grayscale
48 bit color
Adjust scan resolution to
Spatial 150 to 200ppi 144ppi
produce a minimum pixel
Resolution measurement across the
long dimension of 6000
lines for 1 bit files and
4,000 lines for 8 to 16 bit
files.
Spatial 4000 to 8000 pixels 600 pixels across 150 to 200 pixels
Dimensions across the long the long dimension across the long
dimension dimension

7. Digital Imaging Best Practices
MAPS
Master Access Thumbnail
File Format TIFF JPEG JPEG
Bit Depth 16 bit grayscale 8 bit grayscale 8 bit grayscale
48 bit color 24 bit color 24 bit color
Spatial 600ppi 150 to 200ppi 144ppi
Resolution 300 to 400ppi
for larger maps
Spatial 6000 to 8000 1078 pixels 150 to 200
Dimensions pixels across the across the long pixels across the
long dimension dimension long dimension

8. Digital Imaging Best Practices
GRAPHICS
Master Access Thumbnail
File Format TIFF JPEG JPEG
Bit Depth 16 bit grayscale 8 bit grayscale 8 bit grayscale
48 bit color 24 bit color 24 bit color
Spatial 600 to 800 ppi 150 to 200ppi 144ppi
Resolution
Spatial 6000 to 8000 600 pixels 150 to 200
Dimensions pixels across the across the long pixels across the
long dimension, dimension long dimension
excluding
mounts and
borders

9. Digital Imaging Best Practices
METADATA
Descriptive Metadata

Metadata that describes the intellectual content of a resource and

used for the indexing, discovery and identification of a digital
resource.
Administrative Metadata

Metadata that includes management information about the digital

resource, such as ownership and rights management.
Structural Metadata

Metadata that is used to display and navigate digital resources and

describes relationships between multiple digital files, such as page
order in a digitized book or diary.
Technical Metadata

Metadata that describes the features of the digital file, such as

resolution, pixel dimensions and hardware. The information is critical
for migration and long-term sustainability of the digital resource.
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10. Digital Imaging Best Practices
GENERAL PRINCIPLES & SUMMARY
Digitize at the highest resolution appropriate to the source material

Digitize at an appropriate level of quality to avoid redigitizing and

rehandling of the originals in the future
Digitize an original or first generation (i.e., negative rather than print)

of the source material to achieve the best quality image possible. In
the case of art prints, the developed print is considered the original
piece.
Create and store a master image file that can be used to produce

surrogate image files and serve a variety of current and future user
needs
Use system components that are nonproprietary


11. Digital Imaging Best Practices
GENERAL PRINCIPLES & SUMMARY
Use image file formats and compression techniques that

conform to standards within the cultural heritage community
Create backup copies of all files on servers and have an off-

site backup strategy
Create meaningful metadata for image files or collections

Store digital files in an appropriate environment

Monitor data as necessary

Document a migration strategy for transferring data across

generations of technology
Plan for future technological developments


12. Digital Imaging Best Practices
FOR MORE INFORMATION
BCR’s CDP Digital Imaging Best Practices
Version 2.0
June 2008
http://www.bcr.org/cdp/best/digital-imaging-bp.pdf
or
http://bit.ly/NVRd
(capitalization counts)