The Kodak Response: How Long Will Your Pictures Last?
No one knows more about photographs and the people who take and use them than the Eastman Kodak Company. That is why, when it comes to answering the question "How long will my picture last?" scientists at Kodak focus first and foremost on the needs and expectations of the consumer. Kodak scientists have evolved and enhanced their accelerated testing methods to take into account both changes in technology and in the way end-users display and store their photographs in order to deliver the
high-quality images Kodak has been delivering for decades. Specifically, Kodak's testing methods take into consideration:
· How people typically store or display the print;
· The environmental conditions under which the prints are most frequently stored or displayed;
· Which environmental factors most often contribute to image quality degradation;
· The best way to measure the change in image quality that each environmental factor causes;
· How much change in image quality is acceptable to consumers; and
· How to translate the results of accelerated testing to produce a real-world print life estimate.

In determining the appropriate testing conditions, Kodak has conducted extensive studies of the home environment and the storage and display habits of consumers for many years. These studies have been published in peer-reviewed, scientific journals and demonstrate an excellent correlation between the real-world, real-time fade of traditional silver-halide based imaging materials and accelerated fade tests of the same materials conducted under Plexiglas-filtered fluorescent lighting conditions. The findings of these studies indicate that a long-term average light level of 120 lux is a reasonably conservative approximation of the consumer display environment.

Additionally, Kodak recently conducted a detailed statistical analysis of more than 250,000 separate light-level measurements collected from numerous homes in cities around the world. The results confirmed that 120 lux is a reasonable approximation of the long-term consumer display environment. No other company or testing organization has conducted such an extensive study.
Not every print will be displayed in the home environment, and Kodak approaches accelerated light-fade testing with this in mind. In addition to testing for the home consumer environment, Kodak also uses glass-filtered xenon light to better simulate the long-term effects of photographs displayed in a commercial environment. In making these light-fade print-life estimates Kodak approximates the commercial environment illumination at 450 lux.

The degree of acceleration used in light-fade testing can have an impact on the resulting image permanence estimate, with the most accurate results coming from tests conducted at the lowest levels of illumination. Many companies conduct all of their tests at the same level of illumination, while Kodak now uses a variety of light levels to ensure accuracy. Kodak conducts test at 80,000 lux in order to provide results in a manageable time frame, while also testing at 5400 lux to verify the results. As a final test, Kodak uses an "ambient fade" room, which simulates even lower levels of light (~1000 lux) in combination with moderate levels of ozone, temperature, and humidity.

Because not all photographs are displayed behind glass in a frame, lightfastness is not the only factor to consider when it comes to testing for image permanence. Other environmental factors can also play a significant role, especially when photographs are displayed unprotected on a refrigerator or bulletin board. Kodak was the first company to account for the total environment experienced by photographs in its testing procedures, including light, heat, humidity, and air pollutants, such as ozone. Traditional silver-halide imaging materials are really only sensitive to light and heat, and Kodak has long advocated that any print-life estimate for such materials must include results for both factors. However, more recent digital imaging technologies, such as inkjet, have shown sensitivity to all four environmental factors. For this reason Kodak has been at the forefront of developing newer accelerated test methods that take into account all four factors in order to provide the most accurate print permanence estimates.

Kodak Ultima Picture Paper with ColorLast Technology leads the industry in quality and longevity, providing photographs that last more than 100 years when printed with the latest inks. Pictures fade when they're exposed to light, air pollution, moisture, and heat, but Kodak ColorLast Technology shields your pictures from these picture-unfriendly factors. Kodak starts with its industry-acclaimed Kodak Royal Paper as the base and adds a proprietary three-layer coating that controls smudging, speeds dry time, and protects against ozone fade. Kodak ColorLast Technology locks ink molecules into the image layer, protecting pictures from fading factors. Using a unique blend of mordants (additives to "fix" the dyes) in the bottom two layers, along with nanoparticulate ceramic particles in the top layer to further stabilize the image, Kodak scientists have engineered a significant leap in longevity and color reproduction.

Kodak's unmatched heritage in helping consumers preserve their memories relies on extensive research to develop and enhance testing procedures that provide credible estimates for image permanence. With this unparalleled experience and leadership, its products, such as Kodak Ultima Picture Paper offer consumers unmatched longevity for their prints.

About The Author: Joseph LaBarca joined Eastman Kodak Company in 1976 with a Bachelor's of Science degree in Chemical Engineering. LaBarca has spent his entire career in the research, development, and commercialization processes for Ektacolor papers and processing chemistry in both technical and leadership roles. This included extensive involvement in the stability of color papers beginning in the early 1980s and continuing today. LaBarca is currently a Senior Research Lab Manager in the Imaging Media and Materials organization of the Kodak Research Labs, directing a laboratory with systems responsibility for color negative films, papers, and display materials, and is a member of the ANSI/ISO IT9 Committee on color stability.