Digital BW, The Print

pr_roark schreef:
>> ... the fact that different coatings create different hues with
>> mono ink should be a major clue that something delicate, and
>> potentially problematic, is happening chemically at that bond. ...
> 
> I'm not sure whether there is a chemical bond involved.
> 
> Another hypothesis is that the way in which pigments are absorbed or
> spread could affect the hues we see.  For example, with respect to
> the blended carbon + color inks, which include the Piezo inks (aside
> from the carbon sepia), the different pigment types could be absorbed
> differently on the coating.  Early on the way we could tell that an
> ink was not 100% carbon was to put a drop onto a piece of paper and
> the colors would spread and show -- a form of "paper chromatography."
> With the 100% carbon pigments the warmth seems to be an edge affect
> mostly.  Where a paper spreads the ink more, causing more of the edge
> to be semi-transparent, there might be more warmth.  Where the
> droplet is tightly held and does not spread or bleed, there might be
> less warmth.  This might affect the mostly carbon blended Piezo inks
> as well.
> 
> Paul www.PaulRoark.com
> 
> 

Paul,

I would agree on that hypothesis. Depending on how opaque the pigment 
particles are and their size distribution you will see hue effects when 
coatings give different bleedings. It also recalls Tyler's observation 
that matte papers may have a higher optical resolution than gloss 
papers. The contrast possible with gloss papers disguises that.

Smaller droplet sizes of an ink should create more hue shifts too 
compared to larger droplets of the same ink. The total dot boundary area 
increases.

In conventional printing higher resolutions always meant a thinner ink 
layer. It will not be different in inkjet printing. The compromise will 
be in the gamut if the pigment load in the ink can not be increased at 
the same time. The N-color printers have an advantage that ink build up 
can be kept lower  in the substitution of  CMY mixes. The advantage of 
more grey inks for B&W printing will be lost to some extent or the 
darker inks have to start earlier on the tone range. None of the inkjet 
inks is really completely opaque, so a thiner ink layer should affect 
fade properties of the print too.

-- 
Met vriendelijke groeten,   Ernst


Dinkla Gallery Canvas Wrap Actions

|      Dinkla Grafische Techniek      |
|         www.pigment-print.com        |
|                 ( unvollendet )                 |