Digital BW, The Print

on 6/26/02 2:30 AM, Martin Wesley wrote:

> I can see what is happening to the image data with this workflow. I have no
> idea what is happening to the data with the Piezo driver or a RIP.


Martin,

Your post nicely summarizes the landscape here, and I should probably just
let it stand, but I have work I'm trying to avoid. ;-)

I think the above gets to the heart of what my quibble was. There seems to
be an assumption (by many, including myself at one point) that the RGB
workflow is harsher on a file than sending a grayscale file through the
Piezo driver/profile, and I'm just not sure that is the case.

Yes, in the RGB workflow we know the image is tortured by radical separation
curves, but do we know that the Piezo alternative is any less dramatic?
Unfortunately we don't. *Something* is still partitioning those same ink
densities. I'd say the proof is in the output, and we know that both can
fail.

> Posterization can have many sources.
> The most common is probably over manipulating 8-bit files and I think the
> second maybe scanning.

I'll spite myself and go out on a limb and suggest that the inkjet process
itself is the primary cause of the posterization most on this list
experience.

My sense is that since all workflows are working with similar ink densities
and similarly applying those densities across the image, tones that fall
into those density (and sometimes hue) cracks and transitions may fail
similarly with all systems. That all are capable of posterization with
pristine files seems to bear that out.

Now if this were a group of LTV outputters I'd agree fully with what you say
above.

Todd