Digital BW, The Print

Mark,

I downloaded the public Beta of the WIR i*Metric. We've only tested 60 Megalux so far which is equivalent to only 30 Wilhelm Years (450 Lux 12 hours/day) for a PiezoTone CarbonSepia  vs  Epson ABW matching CarbonSepia with the AaI&A 30 patch target on Epson Velvet Fine Art.

At 60 MegaLux:
PiezoTone CarbonSepia average deltaE is 1.36 with worst 10% at 1.92
Epson ABW (mathching CS) average deltaE is 3.37 with worst 10% at 5.93
(the worst 50% of ABW is at 4.96)

So it looks like it's going to be a longevity massacre.

WIR can only test density fade with his current suite of tests but can not detect changes in color balance, which is why the i*Metric was invented. Why he does not implement it is a mystery. I would suggest his 450 year estimates for ABW might be at least 400 years off (as far as photographers eyes are concerned). DeltaE >5 is  easily visible color shift. The mid to quarter tones (L46 - L80) of the ABW are what took the bad hit. We will continue to test until PiezoTone hits deltaE 5, but will give interim for them both. 

If I were you I would not guarantee more than 30 years to your customers before visible color shift on any ABW prints that are Sepia (at least on Epson Velvet Fine Art Paper). The density loss of ABW is minimal, but it won't stay Sepia. I would have expected better with all the published data, although I can not say I am disappointed.  ;)  Nor am I that surprised after reading Wilhelm's account of being "unable to analyze changes in color balance" when testing Epson Ultrachrome K3 inks with the current WIR V3.0 test suite.

It is possible that other Piezography ink matching ABW presets will do better. I suppose it is also possible they will do worse. We are going to match all the possible PiezoTone and K7 ink sets with ABW and run them head to head. I think it is highly unlikely that any monochrome print made by mixing in warming or cooling inks can stand up to a truly monochrome pigment print. It's not rocket science. Carbon is very strong and can be altered towards warm and cool on its own as long as a dedicated ink set is employed. Color pigment is not as strong as carbon. The color simply burns off at a much greater rate resulting in the shift. Because the % of color to carbon is small, not much fade is recorded by densitometry (which is what WIR uses, rather than spectrophotometry which would measure the % of retained color.) Endlessly interesting when you begin to analyze this stuff with actual data.

Jon Cone
InkjetMall.com


--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Mark Savoia <mark@...> wrote:
>
> I have had my Epson 9900 for a few weeks now and was finally able to  
> do some tests to compare its ABW mode vs Piezotone selenium inks.  
> Bottom line, the Piezotones have much more depth to them. They look  
> 3D and the 9900 black and white prints do not. Color on the 9900 I  
> was able to tweak to match the Pieozone fairly close. All tests were  
> done on Hahnemuhle Photo Rag.
> 
> Just thought I would report my results.
> 
> 
> Mark
> http://www.stillrivereditions.com
>