Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@y..., Richard Sintchak 
<richard@c...> wrote:
> Sunday, August 18, 2002, 4:52:53 PM, jrandall1149 wrote:
> 
> j> Richard:
> 
> j> Under a 10x loupe, I typically don't see any dots on the prints 
of 
> j> stepwedges and/or ramps from 0% until about 40% on my 1160.  
Could 
> j> you please post high rez images of stepwedges and/or ramps you 
> j> generate using both PiezoBW and 1160 RGB partitioned curve 
showing 
> j> the dots?  
> 
> j> I know that there is varibility among 1160s, but to have dots in 
the 
> j> highlights using the 1160 RGB partitioned curve is not typical.  
Any 
> j> possibility of noise?  Are you printing on EAM/EEM?
> 
> j> I'd be interested if others have observed dots in highlights as 
well.
> 
> j> Thanks.
> 
> j> Jeff Randall
> 
> 
> Hi Jeff,
> 
> Thanks for your input.  The dots I have seen were not on the
> stepwedges/ramps but on different prints.  When I was first starting
> I printed using both the Piezo driver and Epson driver/Randall curve
> and in a few it seemed in some of the mid-tone transition areas the
> Piezo was smoother.  I'll dig up a couple examples of prints where I
> saw this most evident and scan them as well.  I'll let you know.
> 
> Oh, and yes, for now all I've been printing on is EAM.
> 
> Best regards,
>  Richard  
> 
> mailto:richard@c...

Richard:

If the highlights in the stepwedges and ramps were dotless using the 
1160 RGB Partitioned curves, but actual prints showed dots, I then 
suspect some kind of noise or very high frequency non-uniform tone. 

BTW, the bump you reported seeing in the ramp at about 60% is where 
the Epson driver automatically kicks in the black ink.  I can barely 
see it on my printed ramps, however it has been on my long-range 
radar to improve.  If it is a current problem, you can try tweaking 
the red curve. 

Good Luck.

Jeff Randall