Digital BW, The Print

----- Original Message -----
From: "tboleyyh" <tyler@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Sunday, August 04, 2002 5:42 AM
Subject: [Digital BW] Number of tones was Re: Do inkjets dither or not?


> --- In DigitalBlackandWhiteThePrint@y..., "Austin Franklin"
<darkroom@i...> wrote:
> > Tyler,
> >
> > Before responding to your post, I have one simple question for you.
> >
> > If the file only contains 256 levels of gray, and IF (BIG IF) what you
claim
> > is true, that standard Piezo is capable of 1000 tones, where do the
extra
> > 744 levels of gray come from?  How, exactly, are they derived?
>
> Austin, I honestly can't explain it any better than I did. I really think
you have to think beyond your file, and see the entire
> system including the ink and paper.
> How about this to think about?
> 256 level grayscale file not altered in any way. Printed with a
hypothetical two ink printer.
> Exact same information sent to two mono inks of different density. Is the
tonal scale extended beyond the same thing
> printed with one ink?
> With respect Austin, I think I'm done with this. I also think, with
specific regard to the Piezography driver, someone from
> ConeTech would be far more qualified than I to discuss that system.
> If my previous BS didn't communicate properly that's my shortcoming. If it
did, but is flawed, I'd be interested in hearing
> how.
> Tyler

I was intrigued by a message from Jon Cone several months before Piezography
appeared. He seemed quite certain that the Epson 9000 was capable of droplet
size variations that were not used by the Epson driver but he wasn't certain
how it could be used. That is how I remember the content. Whether he
actually uses that kind of
extra capabilities of the Epson printers I don't know.

It doesn't make a difference on the 8 bit in 8 bit out discussion though.

Krawitz mentions something about the computing in the Gimp print driver;
that to get a better rounding off this is done in 16 bit where the end
result is then brought back to 8 bit figures (something like that). Maybe
Cone just doesn't round off but uses this routine till the end. I don't
think it brings more than a marketing advantage. A 16 bit image could be
handled even higher. Maybe it all is ridiculous because the Epson firmware
in the printer is so limited that no fancy calculations will ever get to the
printhead. There has to be a DA conversion before the heads. If it is
digital till the end then things are different. Frequency can be exploited
when the firmware allows it.

Ernst