Digital BW, The Print

I have seen banding in prints from 8 bit files several times. But
related to one of your comments- contrast manipulation of an 8 bit
original. It's worth noting that there is also loss when editing 16
bit files, it's just that you're usually still left with far more then
256 levels after the fact.
Banding that is not a file problem can occur as well, say from
imperfect partitioning for quads, basically any non linear workflow or
output system. I've seen banded color output caused by bad profiles.
Whether or not some drivers or RIPs actually utilize 16 bit in is
still not certain. Because they may accept it doesn't necessarly mean
they use it.
Tyler

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Pieris
Berreitter" <pieris@y...> wrote:
> 
> Hm, so there are RIPs that print 16-bit images... I know QTR uses
> 8-bit TIFFs and I assumed the Epson printer driver is 8-bit only. I
> had assumed 16-bit workflows are only useful during manipulation, and
> I guess that's valid unless you have a 16-bit RIP.
> 
> Roy made a good point that I hadn't considered: you need to (at least)
> double the number of grays we can distinguish between to prevent the
> eye from seeing banding in continuous-tone regions.
> 
> "Metrology mania" aside, I have so far not seen a case of banding that
> couldn't be tracked back to the image file.
> 
> -Pieris
> 
> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Paul Roark"
> <paul.roark@v...> wrote:
> > Pieris,
> > 
> > >How many discrete levels of gray ... do we get out of a quadtone
> inkjet?
> > ...
> > 
> > I printed a 256 test chart with the C86 and EZ inks.  My X-Rite (DPT
> 22) was
> > able to measure the difference between all the steps with 2
> exceptions.  The
> > top and bottom 2 steps were essentially the same. 
> > 
> > I was amazed at how well the little printer did.
> > 
> > A more interesting question might be whether the most expensive
RIPs can
> > match the C86.
> > 
> > I, for sure, don't have the patience to see if one of the 16 bit
> printing
> > utilities (like IJC) can separate all those levels.
> > 
> > Paul
> > www.PaulRoark.com