Digital BW, The Print

Hi Tyler,

> > and BTW...
> >
> > > ... It
> > > renders more than 1,000 gray values in 8-bit mode.
> >
> > I believe 100, not 1000...you simply can't have more than 256
> values in an 8
> > bit byte...
> >
> > > The new
> > > PiezographyBW Pro24 renders more than 4,000 gray values in
> 16-bit mode."
> >
> > I don't know that is true either...as it's not the number of
> bits here that
> > matters, but the number of inks, and the ability to actually
> dither them to
> > make that many tones...haven written many dithering/halftone
> algorithms for
> > pre-press output devices, I'm very skeptical of the accuracy of this
> > statement.
>
> Austin, starting with a 16 bit grayscale file, then preparing it
> for quad printing though a RIP remaining entirely in 16 bit in
> very much the same way Piezography does for you behind the
> scenes, yeilds a file that has 29,037 "unique colors" (levels).

Well, no, 16 bits is 64k unique levels.  Anyway, that isn't relevant.  The
printer simply can not produce that many different levels, without
sacrificing overall output resolution, and besides, the human eye can
absolutely not discern them.

> This is determined with a cool little utility written by Bruce Linbloom.
> Even after converting it to 8 bit, it reports 1,495 levels.

8 bits only allows 256 levels.  It is PHYSICALLY impossible to get more than
256 levels from 8 bits.

> Keep in mind these are 4 channel files.

No, they are not.  They are B&W files.  Grayscale.  That means only ONE
channel.

> Some of this will be lost
> from channel (read ink) overlap, much will be lost because
> the Epson will round off to make it's dots, some will also be
> lost in the texture of the paper or our inability to determine the
> way an ink/paper combo differentiates those values.
> Even with all that, 4000 may not be an outrageous claim.
> Tyler

I'm going to guess you're not thinking clearly about this, since I know you
know better...

Regards,

Austin