About the same time, Fuji came out with a new, more stable paper. In the 60s and 70s, Fuji paper faded much more rapidly than Kodak paper, and Wilhelm concentrated on Kodak at that time. IDK how well the accelerated tests they use now can be used to predict that, but I'm sure that there is some degree of assurance that todays paper keeps x times longer than the old paper under the same conditions and that can be reported on. I have prints 50+ years old that still look great but are slightly yellow, but it varies)Įndura paper has a projected lifetime of about 200 years according to Kodak's web site. (note that - I'm seeing fade but in the 20 - 30 year time frame. By this time, over 20 - 30 years later, who can tell. It might be the wash water or the batch of paper. Some prints I have kept well and others kept poorly even though all were kept under the same relative conditions. I'm not sure how well anyone's fading tests predict into the real world. Therefore, we found that print fade had a degree of 'reciprocity' built into it as well depending on intensity and duration. Of course, heat and humidity are also significant factors, and oscillations in these cause the effects of light and oxygen to vary. There was a 'relaxation' phenomenon that took place under this type of intermittant illumination. It was found that at that high level we could induce fade very rapidly but there were problems as the actual light was intermittant in a home or gallery and there was consideralbe contribution from oxygen diffusion into the print. When I ran tests on color paper, we used 2000 FCH illumination 24 hrs/day. There must be some sort of standard established, but there is not. The article Robert refers to above from the Wilhelm site is mainly discussing ink-jet or digital papers.
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