Digital BW, The Print

Olivier wrote:
>> On the HP Z3100 models there are just two droplet sizes 
>> available: 4 and 6 picoliter. 
> 
> Ernst, I remember once you mentionned dot gain is "proportionally" 
> higher with small dots than larger ones. My memory is not always 
> correct, can you please confirm.
> Sorry I disturb this discussion, but I wanted to try my luck ...
> Thanks.
> Olivier

This is correct. If there's dotgain as a result of slower 
drying, higher printing  speed, etc then the dotgain will be 
more pronounced with smaller dots than with larger dots for 
the same tone. The boundary of the dot is where the dotgain 
happens, 40 small dots at 30% coverage have a longer total 
boundary than 20 bigger dots at 30%.

This effect is in itself also more pronounced with a high 
contrast black ink with opacity where the dotgain will be 
opaque as well. With the diluted grey inks that have some 
transparency the dotgain will be more transparent + where 
the ink flows from in the dot the dot may get less density. 
Black dots have more buffer so dotgain has more impact with 
black. In detail reproduction both cases are wrong but with 
black dots you also get more pronounced tone shifts.

Met vriendelijke groeten,  Ernst


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