I know Michael was using EEF for some shows at one point. It might be helpful if he would weigh in on this subject as to how those prints are holding up today. This information about the longevity of EEF is quite worrisome for me as I recently printed several large prints with this paper for a gallery.
Based on the AaI&A conservation display rating for EEF, I would not expect anyone to have seen OBA burnout with this paper under typical gallery display conditions since it has only been on the market for a few years. However, one might notice a subtle change of paper color in just a few years in an EEF print framed under glass that is placed in a bright interior display space (e.g. a lobby or atrium in a commercial building with lots of skylights). You can also induce the OBA burnout with ozone very easily for unprotected prints in just a matter of weeks or months, plus if you try the proverbial artist's "window fade test" in a south facing window, you should be able to see the OBA burnout effect in a matter of weeks.
That said, it is instructive to put all the longevity information we have on EEF and other papers into perspective. EEF does indeed underperform in Aardenburg testing compared to other "traditional fiber" type inkjet papers the printmaker might choose, and the reason is it's reliance on very high levels of OBA to get the nice "cool bright white" appearance that many people love about EEF. Yet when using Epson Ultrachrome ink sets it still achieves similar or better scores compared to other widely used and highly esteemed processes in photography (e.g., Lambda and Lightjet prints made with Fuji Crystal Archive paper). So, as long as the collector is informed about the limitations of one's chosen print process, appropriate care can be taken to ensure many decades of display where the print will remain in excellent condition.Light Fastness Ratings are designed to be quantifiably objective, but the criteria that give rise to these ratings are definitely subjective:
WIR rates EEF at 90 years of "display life" using any of the Epson Ultrachrome ink sets (k3, K3VM, HDR) when the print is framed under glass. AaI&A rated one publicly accessible sample made on an Epson 4800/OEM K3/EEF system at 29-79 megalux hours of light exposure for a print framed under acrylic glazing. Acrylic has more UV absorption than glass but not so complete as to totally shut down OBA fluorescence. Other EEF samples in test at AaI&A with various Epson Ultrachrome ink sets have generated similar scores. This megalux hour exposure range translates to the WIR "display life" time scale of about 15-40 years. Other than the minor glass versus acrylic differences in the rating methods and some differences in light sources used by the two laboratories, why is there such a large apparent discrepancy between the two laboratories' rating results? A major reason is that AaI&A Conservation Display (CD) ratings are based on visual criteria to show "little or no noticeable fade"
whereas WIR ratings are based on visual criteria that show "easily noticeable fade"
. Both of these subjective visual endpoints for allowable fade are justifiable, and we actually need to look at more than one point on the fading curve to fully characterize a system, but IMHO, Aai&A CD ratings are more suitable for fine art applications while WIR ratings are entirely appropriate for consumer photofinishing applications.
Another important distinction between WIR and AaI&A ratings is that WIR, indeed all other testing labs other than AaI&A, rates the product performance according to a single limiting factor
being exceeded in the test, whereas AaI&A expresses a lower limit and an upper limit in its conservation display (CD) ratings
. The range expressed in AaI&A's CD rating reflects a real world reality that our ability to notice fade in a specific print on display is in fact image-content dependent. For example, if OBA burn out is a weak link in the system and the media color starts to turn yellow, the viewer will observe the change sooner in an image with large areas of highlight colors (e.g., a white wedding dress) compared to, say, a borderless framed print of a landscape scene that may have some specular highlights but no dominant areas where media discoloration can easily show through.
Suffice to say, OBA burnout rarely triggers the WIR "paper discoloration" limit factor because the WIR criteria were originally developed for traditional color process where yellow stain formation in the highlights, not OBA burnout, was a major issue that consumers were first likely to notice. On the other hand, OBA burnout, paper bleaching, and other subtle modes of discoloration are definitely picked up and factored into AaI&A test scores because the AaI&A criteria for allowable changes use tighter visual limits based on CIELAB colorimetry. My contention is that if artists and collectors can see and appreciate the initial differences in paper white color between slightly cool white papers and slightly warm white papers, then fade test criteria suitable for fine art applications should be able to identify and distinguish papers that change from cool white to warm white or vice versa during testing.
Lastly, I would add that the OBA burnout performance for EEF is not unique by any means. For example, if you check the CD ratings in the AaI&A database for Hahnemuhle Fine Art Baryta (a relatively bright white paper), you will see comparable performance to EEF when printing with Epson OEM ink sets. Most inkjet paper vendors are trying to provide a wide range of media colors and surface textures based on market research concerning customer preferences and tastes, so there are plenty of bright white and warm white papers out there, plus many in between. Only way to know for sure about media white point stability is to test it.