Digital BW, The Print

Ernst Dinkla <edinkla@...> wrote:
>
> ... it would surprise me if 16-bit K7 isn't over the top 
> considering the actual resolution + tone reproduction of 
> the best paper coatings we have.

I was looking just at the resolution issue with different papers, using a traditional line pair/mm type of test file.  The lines were pure black and pure white, producing no information about what happens with gray values.  At any rate, a few tentative conclusions I reached were that bleed (from the black boost and otherwise) and printer limitations may be significant factors.  For what it's worth, I've posted a Jpeg of the 4800 dpi scan at 
Arches-PaSmFa205-IlfSmGloss-4800scans-720-res.jpg

The papers are Arches un-coated watercolor paper, Premier Art Smooth Fine Art 205 (Epson Scrapbook paper), and Ilford Gallery Smooth glossy.

With Arches uncoated watercolor paper I had previously found that holding down the midtone ink limits was critical.  So, for the best Arches print, I suspect I'll need the full Eboni-6 as opposed to the Eboni-4 that, on coated paper, I find visually equal to Eboni-6.  When the ink limits are held way down to avoid bleed, paper overload, and visible dots the need for the lighter inks and the full 6 dilutions is much greater, and the "serial" (?) partitioning of QTR's standard profiling makes a better print than when I use various options to have more inks firing at the same time.

Aside from bleed, I think we may be at the printers' limitations to lay down accurate dots.  The Epson 1400 I'm using is getting old, and that could also be a factor.  (Having made a few trips into the High Sierras on a mule probably hasn't helped this old workhorse of a printer either.)

I also made test prints with Epson Claria K on glossy paper.  While prints from the Noritsu-based similar dyes look sharper than the glossy pigment prints, on the test charts the pigments look sharper -- not sure if this is bleed or some other factor. 


> ... I have not seen MTF charts of inkjet papers/inks/printers ... 

That would be interesting.  I don't think measuring MTF would be within what most of us could do.  As a substitute, and similar to what the pre-MTF lens testers did, I once printed a resolution chart that used a midtone value (like 50%) as opposed to the pure black (100%) lines.  It could provide at least one more data point.  I can't find that now, but my vague memory is that is was similar to the results with the black line chart.  

(I'm now looking at a different issue.  The Eb-4 tests look totally different now than a week ago.  We're in a rain storm.  Does humidity make a huge difference in dmax and tone due to the coatings' inability to hold as much ink?  Sometimes I want to dust of the enlarger...)

Paul
www.PaulRoark.com