--- "Gary L. Hunt" <glh@srv.net> wrote: > Side A: > >>The problem with your theory of air exposure as the primary fading > >>mechanism is that controlled tests have found that prints exposed to > >>light fade much faster than prints kept in the dark, but otherwise > >>under similar conditions. > > Side B: > >I don't know whose "controlled" tests found this to be true, nor how > >"similar" were the conditions of dark storage (were the control prints > >sealed hermetically from the effects of the dark storage ambience?). My own > >"controlled" tests suggest that air exposure is of very great importance. > > I'm kind of beginning to wish this discussion didn't remind me of the > American Cancer Society and the American Heart Association debating > over which disease is the most important killer. I find it hard to see this > as an either-or thing. There is a huge weight of evidence that shows > that increased exposure to light will cause prints to fade faster, Gary, Where is this evidence? There are controlled lab tests that rate ink/paper for longevity based on light exposure. But where is the evidence that concludes that light exposure is more critical to print life than air exposure? From everything I see, it has been assumed that light exposure is the dominant mechanism. Therefore, it has been tested for. The common belief was that it was UV light causing the problems. But Wilhelm suggests that visible light is the main problem. He concludes that laminating doesn't help. And I agrre that it probably doesn't help protect against fading due to direct, high intensity, light exposure. In this application, I agree that light will be the main cause of fading. But in applications where prints don't experience direct sunlight, my evaluations lead me to believe at this time that air exposure is the main problem. Else, why would protected prints last so much longer than unprotected prints in the same, no direct sunlight, environment? and > almost everyone has seen practical examples of it--which would > appear in no way to negate the possibility that air exposure can have > a significant effect even in the absence of strong light levels. (Not > my air, mind you--I live in the middle of nowhere in Idaho. But the > rest of you may have to worry.... (:>) At this point, I believe there is a cross over point. Above certain light levels (direct sunlight for example), light is the main culprit. Below certain light levels (indoor non direct sunlight for example), air exposure becomes the main source for fading. > ===== Visit my digital photography web site along with a lot of other interesting stuff at http://greer.simplenet.com. Also, Greer and Associates (http://www.greeraa.com) offers studio photography, digital imaging services, web site design/construction, and training. Mike Greer __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com - Please turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for instructions.