Digital BW, The Print

Hello Tariq,

>My guess is that visibly, many people are attracted to BO prints 
>solely due to this increase in Contrast.
>Any Thoughts on this?

It's more than just contrast.  Contrast can be increased in full ink
sets as well, if desired.  BO has two attributes that make it very
attractive visually, better Dmax and better luminance.

The Dmax is better because the other UT systems hold off on using the
Eboni until image values are RGB 1 or 2 (about 99.5% or so).  So
anything not quite pure black is rendered with other inks.  In BO,
paper white specks completely disappear at about 95%, and apparently,
further density is achieved by increasingly overlapping dots which
increases the ink density (just my guess as to how it works).  But
there is visible separation in the 95-100% range, and all these values
are rendered with the pure black ink.  This gives a very intense Dmax
and good shadow separation (BTW, these remarks are in reference to
matte papers and Eboni black.  The UT inks on glossy papers are
getting deep Dmax without Eboni).

The luminance is caused by the uncoated paper showing between the
dots.   Paper white specks begin appearing at around 95%, so the
paper's reflectivity is an active ingredient in most of the image.  In
the full ink systems, uncoated paper isn't visible until image values
are up around RGB 254-255.  So BO prints have a gorgeous glow to them
which full ink systems can't match.  The glowing silvery upper
midtones are quite addictive <g>. 

The result is prints that really "pop" in a way that isn't just
contrast.  There is a light quality about them that is distinctive.  I
love it and BO is my first choice.  Only with certain images that are
too weakened by the graininess do I use something else.  


Regards,
Clayton


Info on black and white digital printing at    
http://www.cjcom.net/digiprnarts.htm