Digital BW, The Print

Hi Clayton,

Thanks for your reply.  I'm currently using QTR and making my own custom curves which 
utilize just the Original Epson UC Matte black and Light Black.  One can specify how much 
ink is laid down and the interacting curve in QTR and I'm getting the maximum(and same) 
D-max using either QTR or BO.  

The luminosity you describe vs. overall contrast is more akin to local contrast - the 
contrast within a certain range of tones if you will.  One can manipulate and alter this via 
curves.  I'm sure the paper white that shows more through BO printing due to the lack of 
actual subtle highlight tones created by the ink also alter the local contrast in that range, 
not just the overall contrast.  My point is simply that one could replicate the tonality of BO 
printing if so desired through the use of both curves and the control of the ink laid down 
BUT I'm not convinced that the opposite is true - BO printing can't match the subtle 
highlight gradation if more than one ink is used. THere is just less to work with.  

Tariq
 
--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Clayton Jones" <cj@c...> wrote:
> 
> 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