Or it could be that given inherent limitations of the testing methodology that surely exist but we don't know much about, perhaps we should treat all these numbers as indicative and not fret over fine differences, or depending on context even some large ones, between them. To me, whether the number is 43 or 56 doesn't matter - it just tells me that deterioration shouldn't begin under those display conditions until roughly half a century has passed. Again to me, whether a dark storage number is 200 or 300 doesn't matter because my grand-children will be long gone before the lower limit kicks in - and when it does, what will be the rate and character of deterioration? Who knows. Maybe those of us who have been playing with numbers and forecasts for many decades just become a bit jaded and circumspect about how much precision we should impute to them, especially when we have the opportunity to find out how wrong they've been. Sorry if this sounds a bit dismissive, but you know, there comes a point when common sense and a healthy dose of circumspection must intrude on pseudo-precision just because "the numbers come out that way". I expect opprobrium will come crashing down on me for making such suggestions, but I'll still remain skeptical about the merit of obsessing whether my prints will remain unaffected over generous ranges of these estimates emerging from the tests, useful as they are for indicative purposes.
I can see how you might take that attitude Mark, however, without any "opprobrium" or whatever intended, I respectfully disagree. Looking at Ernst's compiled numbers:
1 HP Vivera (test ended 2012) 11 samples, average 74.
2 Epson HDX (test ended 2018) 9 samples, average 66.
3 Canon Lucia old (test ended 2012) 11 samples, average 57.
4 Epson K3 (test ended 2012) 11 samples, average 36.
5 Canon Lucia Pro (test ended 2018) 9 samples, average 33.
There is certainly a huge disparity between Canon Lucia Pro (33), Canon Lucia Old (57) and HP Vivera's stellar 74. No contest actually.
Same with Epson Vs. Vivera.
I disagree that deterioration won't occur until half a century has passed. Given that there is no equality in how prints are stored whether archival, or not, framed archival, or not, or hung in ideal conditions or not, will significantly impact the longevity of the print, and most pointedly will impact the speed and manner in which the print begins to fade.
One of the most important aspects of fading that Mark McCormick of Aardenburg Imaging has been discussing is the manner in which the print declines and how some ink/paper combinations decline or fade gracefully as opposed to how other ink/paper combinations reach a point and just drop off a cliff declining terribly. It's not pseudo-precision regarding numbers, mainly because they indicate fading under in many ways the best of conditions as opposed to real life conditions that intrude upon the projections. When the numbers reflect comparative realities, they indicate the same proportions under the most adverse conditions.
So actually, I believe we should be much more concerned about whether our prints age gracefully or they drop dead like flashlight batteries.
And also, to be considered is whether the prints are viewed in the context of typical average ownership or in a museum context, and all in-situ scenarios in between.
We don't have those facts and figures in front of us, but as long as we're pseudo-extrapolating, perhaps we should look to someone who has a handle on those projections for answers.
Just my perspective, sir, YMMV of course.
As for me, I'll stick with Vivera, and the highest numbers, top scores, and prints that I believe look the best to my eye, comparitively.
Mark
