Digital Prints

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Mastering Digital Printing
Accelerated Testing Standards
Since real-time observation of print deterioration is, for the most part, impractical—the
products used to make the print would be off the market by the time the test ended—
accelerated tests have been developed to help us out.
The basic idea is simple: By using high-intensity light and/or any of the other influencing
factors, the tester can speed up what would normally happen to a print over the course
of many years.
While there is currently no single, universally accepted testing standard that applies to
print permanence, there is a long history of testing methodology that guides today’s testers,
and several organizations have developed scientific procedures and standards for different
kinds of permanence tests. Unfortunately, they’re all different! The two most important
types are the ISO/ANSI and ASTM standards.
ISO/ANSI
The International Organization for Standardization (ISO)—and formerly the USAmember-body
organization American National Standards Institute (ANSI)—have been
developing or promoting standards for the testing of everything from toothpaste to photographic
film for decades. The older standards ISO 10977 (1993) and ANSI IT9-9
(1996) deal with photographic color image stability, and they regulate such things as the
preparation of test samples, how the tests are to be carried out, how the temperature and
humidity are to be controlled, and how the results are to be evaluated. An updated standard
that deals specifically with photographic images is currently being prepared by ISO
committee WG-5/TG-3 (ISO 18909). With Steve Puglia of the U.S. National Archives
Figure 5.5 Part of a waterfastness test
from the author’s testing of several
inkjet papers. Top: portions of the
print tests were cut out and immersed
into separate containers of water.
Bottom: After only 24 hours of water
immersion, the differences were
striking among three different
ink/paper combinations.