Digital Prints

as its chairperson and Henry Wilhelm as its secretary, the group is working on a new set
of standards (tentatively titled “Methods for Measuring the Stability of Color Pictorial
Images”) that will finally cover digital prints.
The new standards, which supposedly will still focus on print-life predictions, will be
released in stages over the next several years. This ISO group represents most of the heavyhitters
in the digital printing field (Kodak, Epson, HP, Canon, Ilford, Agfa, DuPont, Fuji,
et al.), so they move very slowly and very carefully with so much marketing power at stake.
ASTM
ASTM International (formerly the American Society for Testing and Materials) has been
in the testing business since the late 1800s, but their work in developing standards for testing
art materials is the most relevant here. Their subcommittee D01.57 on Artists’ Paints
and Related Materials developed the D4303 standard that describes the basic method to
test the lightfastness (only) of artists’ paints including oil, acrylic, alkyd, watercolor, and
gouache. (They have also created standards for colored pencils and soon, pastels.) The
D4303 standard requires that colors be subjected to a specific amount of irradiation (measured
in watts per square meter and megajoules per square meter, not lux) in several tests
using different light sources including xenon arc and outdoor sunlight in Florida and
Arizona. Each paint or pigment can then be assigned a lightfastness category based on the
Delta-E difference between samples before and after exposure. Walk into any art supply
store, pick up a tube of paint, and you will see written “Lightfastness I” or similar. That
is the result of ASTM testing.
Even more interesting to us is the fact that this same group is now developing a draft of a
standard specification for printed color digital imagery (primarily inkjets) that will include
some form of the ASTM D4303 standard. Under the guidance of the subcommittee’s chair,
Mark Gottsegen, ASTM is getting the ball rolling with a demonstration (“ruggedness”)
round-robin cycle of tests on a small selection of inkjet samples (see Figure 5.6).
Chapter 5 ■ Determining Print Permanence 161
Figure 5.6 Preliminary portion of a
table-top xenon arc test (with before
and after color patches at right) of a
few digital and photographic
ink/media combinations. This is just
the first of 27 total round-robin test
results that would ultimately be
averaged and published as a
demonstration of what ASTM's testing
standards can provide to the digital
imaging community
Courtesy of Mark Gottsegen