Digital BW, The Print

I have test strips from, first, a 4000 that was printing with a new
neutralized LK (LK-N2a beta) that I mixed that is more appropriate for
midtones and highlights, and, second, a 4800 using the ABW mode, both on
EEM-EAM.  I was curious how the smoothness would compare, especially where
the 4000 print was composed of just the LKN without the aid of the LLK and
light color inks the 4800 adds.  While the 4000 would have the disadvantage
of no truly light inks, it would have the advantage of the color inks being
pre-mixed.  Thus, there would be no bright color dots.

 

I scanned the prints at 1600 optical dpi in RGB.  The settings for the scans
were manual and held constant.  I measured "smoothness" by using the
Photoshop CS2 Standard Deviation.  (I don't really know how this would
compare to how our eyes see, but at least it is an objective measure.)

 

The 4800 test strip was a bit warmer, meaning it would have fewer color dots
than one that is as cool as the LKN.  

 

Nonetheless, at 10%, 25%, and 50% (and presumably at all around those) the
CS2 histogram indicates that the 4000 LKN has a lower standard deviation
than the 4800.  While the LKN scan visually has more bright-dark fine
contrast, the color contrast of the 4800, at least in the CS2 SD
calculations, outweighs the greater LKN light-dark contrast disadvantage.
Only at 5% did the 4800 show a slightly lower SD.  (I didn't measure every
patch.)  It appears, however, at 5% the 4800 is 100% color ink.

 

I'm not sure what it all means, but I'd think it shows what we probably
intuitively suspect: pre-mixing the color inks into the carbon inks produces
a smoother print.

 

Paul

www.PaulRoark.com <http://www.paulroark.com/>  

 

 



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