CASE FOR CREATING A RICH
There are compelling preservation, access, and economic reasons for creating
a rich digital master image file (sometimes referred to as an archival
image) in which all significant information contained in the source document
Creating a rich digital master can contribute to preservation in at least
Protecting vulnerable originals. The image surrogate must
be rich enough to reduce or eliminate the user's need to view the original.
Replacing originals. Under certain circumstances, digital
images can be created to replace originals or used to produce paper
copies or Computer
Output Microfilm. The digital replacement must satisfy all research,
legal, and fiscal requirements.
Preserving digital files. It is easier to preserve digital
files when they are captured consistently and well documented. The expense
of doing so is more justifiable if the files offer continuing value
A digital master should be capable of supporting a range of users' needs
through the creation of derivatives for printing, display, and image processing.
The richer the digital master, the better the derivatives in terms of
quality and processibility. User expectations will likely be more demanding
over time--the digital master should be rich enough to accommodate future
applications. Rich masters will support the development of cultural heritage
resources that are comparable and interoperable across disciplines, users,
Creating a high quality digital image may cost more initially, but will
be less expensive than creating a lower quality image that fails to meet
long-term requirements and results in the need to re-scan. Labor costs
associated with identifying, preparing, inspecting, indexing, and managing
digital information far exceed the costs of the scan itself.
key to image quality is not to capture at the highest resolution or bit
depth possible, but to match the conversion process to the informational
content of the original, and to scan at that level--no more, no less.
In doing so, one creates a master file that can be used over time. Long-term
value should be defined by the intellectual content and utility of the
image file, not limited by technical decisions made at the point of conversion.
No More, No Less: As
resolution increases, image quality will level off.