Efillink.com CIS

Started Jan 29, 2007 | Discussions thread
Mark McCormick Senior Member • Posts: 1,136
Re: Try this!!!! Cheaper by far, too!

Zone8 wrote:

... and a test in full Spanish sun for 3 days has shown no fading whatsoever. I have over many years found this is a severe test (Canon originals did not even last one day!).

Yes, a severe enough test for fugitive dye-based inks, but not actually all that challenging for moderately or highly lightfast inks on decent paper. You would need to extend your test time greatly to produce just noticeable fade in a good pigmented ink system. I'm generously figuring your test condition at 100,000 lux full sun for 10 hours per day x 3 days = 3 Megalux hours of exposure. This exposure dose is equivalent to 1.5 WIR years of display (450 lux for 12 hours per day extrapolation) or roughly 6 Kodak years on display (120 lux for 12 hours per day). You do have more UV content, and you also have higher temperature but much less moisture (the heat causes moisture loss), so all in all, let's also assume that your test condition produces about 2-3 times higher fade rate than the equivalent "under glass" laboratory exposure dose using cool white fluorescent lamps. Hence, I estimate your total test time and conditions to equal approximately 3 - 7.5 "WIR display years".

That said, today's industry-sponsored ratings typically base the predictions on "easily noticeable" fade whereas you noted little or no noticeable fade in your experiments. I, too, prefer ratings based on little or no noticeable fade because they seem wholly more appropriate for serious printmakers, collectors, and museum curators. A rating for easily noticeable fade cannot serve as a relative rank score for the period of excellence in image quality retention because many systems fade non linearly.

To further help put your sun test in perspective, in my tests using "little or no noticeable" fade as the rating criterion, OEM pigmented inks from Epson, Canon, and Hp on good papers routinely exceed 30 megalux hours of exposure in test, and some ink/paper combinations are now past 100 megalux-hours of exposure with their visual appearance still remaining in excellent condition. You'd need at least 30 full sun days to get into that exposure range, and in all likelihood it might take several months of outdoor exposure to accumulate this much light exposure.

best regards,

-- hide signature --
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow