Digital BW, The Print

Tyler,

I was there and did that right along with you - two "P.O.'d" people 
on one of these lists with no one right there to temper them can get 
a little out of hand. At this point, No harm, No foul.

My understanding of dithering, at the driver level anyhow, has more 
to do with blending the dots to get as close as possible to a 
continuous tone. Since the Piezo driver controls the head movement so 
tightly if it were to dither it would actually run the dots together 
causing a loss of detail. The driver places these dots as close 
together as possible while maintaining the tiniest of space to 
simulate a continuos tone. I have two theories about what the driver 
does in this regard:

1 - Jon has tapped into a version of the variable dot technology, not 
quite the same but close (the older models don't have the split 
droplet technology in the heads). This may partly explain why the 
1160 exhibits the window screen pattern since the driver is combining 
a similiar technology.

2 - By bypassing the dithering in the Epson driver and replacing 
the "progressive" nature of the driver he is actually firing the 
nozzles in a linear fashion in the same row. When this is combined 
with what I mentioned in 1 above the Piezo driver actually does the 
same thing in one row of nozzles that the Epson driver does in 
multiple rows while dithering. This allows the increase in dpi (at 
least in the older models). The Epson driver dithers intentionally to 
hide the misalignment that may exist between the row of nozzles as it 
progresses through the print as well as less than perfect feed. This 
may also partly explain the banding that takes place when the feed is 
not dead on, since the dithering is not there to hide it.

Just my theories and I may be a mile off. Make sense?

Terry

--- In DigitalBlackandWhiteThePrint@y..., "Tyler Boley" <tyler@t...> 
wrote:
> --- In DigitalBlackandWhiteThePrint@y..., "TerryR" 
<terryr1028@h...> wrote:
> 
> I don't know what to make of that quote, it seems to contradict 
itself. They say they don't dither dots but also say the dots 
> are tightly packed! It's gotta make dots, or some pattern to map 
pixels to firing nozzles. Perhaps you could call it 
> screening, I've always seen it refered to as dithering in any 
discussion about drivers or RIPs.
> In the spirit of leaving the last few days behind, please don't 
hold me too responsible for what I've said when P.O.'d...
> Thanks Terry.
> Tyler
> 
> > Tyler,
> > 
> > This is taken directly from the Inkjetmall site:
> > 
> > The Piezography BW driver changes radically the way the printer 
> > prints.  The dots are packed as tightly as the print head will 
allow 
> > from 1% to 100% black.  Instead of dithering dots like a CMYK 
driver 
> > does - the volume of ink is changed to vary the ink density.  
> > 
> > 
> > The above cut and paste job is from the site and my understanding 
of 
> > how the Piezo B/W driver works also is in agreement with that. 
That  
> > is what lead to my statement. Maybe we have a different meaning 
> > of "dithering"? If so I would like to understand what you were 
trying 
> > to say.
> > 
> > Thank you,
> > 
> > Terry