In my opinio, Aardenburg is a whole new paradigm shift in longevity testing. He was hired to try and fix the problems encountered by the WIR methods years ago. For whatever reason - the WIR methods are still in place. EPSON uses them. Pays for them. And gives their ratings based upon the WIR version 3 methodology - even though WIR admits that they have lost the ability to analyze changes in the modern Epson ink sets that contain more than 4 ink positions when they use the WIR methods. The WIR method ONLY tests a patch of cyan, magenta, yellow and black and then reports when one patch has faded 35%. So therefore an EPSON rating is based upon 35% density loss of one of those 4 patches. There is no effort with the WIR method to measure for color shift. There is no method to test for shifts to gray balance, flesh, reds, greens, blues, you name it. The only result is that one of the four ink patches faded 35% and it takes X years for that to happen.
The Aardenburg method uses a color spectrophotometer to measure not only density - but also color on more than 30 patches which include paper, neutrals, flesh tones, colors, etc. This is the huge paradigm shift. WIR testing is in effect - color blind and fully density based. While that worked for photographic chemical processes that used 4 dye layers (CMYK) - it does not work for modern inkjet sets. Aardenburg also sets the criteria from 35% fade to about 5% fade which it believes its interested audience can see. EPSON believes that its audience requires a loss of 1/3 before its customers will notice fade. And probably - the average EPSON consumer does require that much. Photographers and fine artists are more visually aware. 5% is about right.
The PASS signifies that the results are for an ink set that does not lose color shift or density at that point. But the real information is in the downloaded PDFs and well worth the price of membership. The Piezography CARBON ink sets are at 200 megalux and totally unmoved. But of course that's CARBON. The universe is made of it. Other Piezography ink sets have a wide variety of ratings because the system is so sensitive that in the case of many tests the paper faded very quickly and that triggered a fail mark. While all Piezography inks are made of carbon and carbon based pigments - the CARBON ink set is never going to be affected by something as benign as light. But, all of these piezo tests are worth downloading to see that the density of the inks is extraordinary. Mark has said that any of the Piezography ink sets will last more than 100 years without visual density loss. The CARBON ink set on the other hand, is in a league all of its own. It loses no density - but also no color.
A Selenium ink set will eventually reduce to its carbon component. No density loss - but at some point the color begins to shift subtle.
The Aardenburg results are based upon length of exposure and loss of color and loss of density. With the EPSON test - you have NO IDEA when the results faded 5%, 10% or 20%. You only know that in XX years it will fade 35%. But, what if your target was 10% fade and you would accept a 10% fade. Would you want to know that an Epson ink faded 10% in 5 years? That is just for illustration. The Aardenburg method gives ratings every 10 megalux which is about 10 years indoors. And you can get an idea of the density loss or color loss you are willing to accept.
WIR is allowing beta sites to use a similar technology as Aardenburg. In all practicality it is the exact same technology because it was developed there. We are a site for this and we do our own i*metric testing on our inks. For our new Claria replacement - we have decided to mix the EPSON 35% results with the i*metric. Rather than compare 5% fade results to 35% fade results - we are allowing our targets to be faded to 35%. This way we have a more direct comparison to the Epson Claria ratings. We've been testing now for many many months and we have a very good picture of our inks side by side with Epson Claria.
What does it all mean? You should become a member of Aardenburg. You should understand Epson ratings for what they are and not draw conclusions that they mean that your work will not fade. The Epson ratings are more of a guarantee of horrible fading at that amount of years - and you have no idea whatsoever how bad they will be prior. Aardenburg tests give you a year by year roadmap of what to expect in 10 years, 20 years, etc etc...
Unfortunately - ignorance is bliss. Epson ratings are like "things go better with Coke". It is a perfect marketing slogan. 100 years! Sounds like a long time - and feels like a sure bet. But 35% fade is not something you want to communicate to your customers. Aardenburg has their work cut out for them - because it forces consumers to think and forces them to choose what longevity they really want.
Having said all that - most people want to accept the 100 years of Epson and then not accept the blame for when the work fades 10 or 15% in a fraction of the time they guaranteed their customer. THey have Epson to fall back on. Epson has WIR to fall back on. The WIR methodology only indicates "easily detectable fade". Who is going to argue with that? Things do go better with Coke!
With Aardenburg - you get facts. But you need to dig down. It is a far superior method if you can understand it and its worth being a member because your support is what makes that happen. Aardenburg does not allow manufacturers to submit. Only consumers can. WIR does not allow 3rd party inks to be tested - only the OEM can pay for those services. So Aardenburg obviously is on your side!
There are two interesting tests in place now on Neutral. One test has a premature failure - one test is at 40 megalux and still going. The subtleties of paper OBAs are actually a huge component of these tests. You can have a long lasting ink but put it on a paper that is totally crap. WIR can not measure for OBA failures. It's all very very interesting.
What WIR has and continues to contribute is a vast history of knowledge about why inks fade and what contributes to it. Henry is extraordinary. I am sure that if the OEMs wanted to use i*metric and reduce their customer's expectations - WIR would be publishing it. AS it is - i*metric is only in limited use now at WIR. It is in full swing at Aardenburg. I would not want a world without Aardenburg or WIR. The OEMs finance WIR. You need to help contribute to Aardenburg. So get over there and pay the small fee he asks to download the pdfs. And yes - you can submit tests!