I always was thinking that metamerism is caused mostly by inks. From my experience with Epson 2200 OEM inks it seems to be true: you could take paper like Silver Rag (no OBA) and still have the same color shift when printed with those inks. Effect was most pronounced when I tried to do B/W photos using these inks, which is understandable.
Normally manufacturers enhance absence of OBA in their ads, for me the rule is: "bright white" = OBA added, "natural" = no OBA. Many decent papers have both versions.
there are many contributors to metamerism failure, OBA content is probably one. More important though are other factors like GCR. A 2400 with an additional light light black and higher gray component replacement in the driver will deliver a print with less metamerism failure than the identical Ultrachrome image on the same paper but made on a 2200, which has one less light black ink, and less GCR in the driver (OEM). Then with a RIP, the same ink and paper as the 2400, I can make an ink setup and CMYK profile with even greater GCR, therefore still less metamerism failure.
We used to think dye inks were poor performers in this regard, but then in those days we also had less light black inks and far less GCR, so it's hard to say. On the other hand, the Lyson dye quadtone inks and small gamut inks had the worst metamerism failure I have ever seen, and they were extremely low gamut inks...
So the only way to evaluate OBA content contribution would be to put two papers with and without up against each other with all other factors being equal.
Crane Silver Rag and Museo Silver Rag are the same, Intellicoat bought Crane's inkjet paper line.
Tyler http://www.custom-digital.com/
And thanks for the info about Museo. And even more importantly, thanks for introducing these printing terms. There's so much to learn ! Yet another vital link in the Chain of Quality.
I found them in the Color Terms article on adobe.com
UCR or Under Color Removal: When color separations are made,the combination of colors might exceed the Total Ink Coverage value for a certain press and paper, so the ink will not dry. UCR compensates for the excess by removing small percentages of ink.
...as opposed to
GCR or Gray Component Replacement: A method for replacing neutral grays made up of combinations of cyan, magenta, and yellow with a similar value of black ink.GCR improves the printability of a job by making neutral grays easier to balance on press.
UCR describes a typical color separation, where GCR describes a more sophisticated separation process where neutral colors are modified and substituted by black ink.
The 2200 has metameric failure in many of its prints, due to the number of inks and the proportions that the printer uses to create colors. As much as a 20 point shift from UV to Tungsten is the result. Although the Hahnemuhle Photo Rag has OBA's the content is "very low" and we have had great results with it. If the paper is a commercial paper like Epson glossy or anything that looks blue, I would stay away from it if you are concerned with Metameric Failure. If a paper has a very low amount of OBA's you will be fine in terms of metamerism and longevity. But it also depends on the quality of the printer being used.
"The Hahnemühle papers William Turner (category 1, no optical brightener) and Photo Rag® (category 2, a minimum of optical brightener) have been tested in combination with the new Vivera inks from HP, at the renowned Wilhelm Imaging Research Institute Inc. Over a simulated test period of 200 years no appreciable change in the whiteness of the paper was detected. Even in the case of the papers belonging to category 3, the bright white papers, after testing by the German FOGRA institute remained stable for a test period of between 20 and 50 years."
Last edited by PAllen; 30-Apr-2010 at 10:15.
Reason: Patrick Allen www.KenAllenDigital.com www.PatrickAllenPhotography.com
I know you do mostly BW. I was not happy with my 2400 and ABW. I am much happier using bw inks although I am limited to matte papers with the current mix I use. Also, a CIS system will save a lot on ink costs. Watching those printer carts exhaust themselves in cleaning cycles is painful. When I installed a waste ink external tank, I was amazed how much ink is wasted.
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