Digital BW, The Print

I've been trying to figure this out; maybe someone can help:

Mostly I shoot/print still life, landscapes, other inanimate 
objects.  I've been printing with an Epson 1280 using MIS Full 
Spectrum inks with the ConeTech Piezography driver for a year now.  
Terrific results on everything until now.

I got suckered into doing some student photos at a local private 
school.  Made the exposures on 35mm TMax 400.  Scan with Nikon Super 
Coolscan 4000ED.  Print as described above.

I've noticed some, not all, skin tones get really mottled or 
posterized in the prints.  Several of the girls have large splotches 
around eyes and nose.  Also, arms and hands seem to be common spots 
for this to occur.  The mottling seems to occur in 30-40% grays, but 
the print darkens them up with the splotching.

I've tried:  Nozzle check with Head Cleaning (All A-Okay);
Printing a test gradient from 100% to 0% Gray--looks great!
I rescanned a couple problem images at 16bit and the problem was 
still there in the prints.

Is it possible to make Curves adjustments that look Fine on screen 
(even at 100%) but contain too radical of shifts for the Piezography 
to handle?  

Any other suggestions?  Help?

Thanks!

Chris
http://wwww.petroscans.com

>Is it possible to make Curves adjustments that look Fine on screen 
(even at 100%) but contain too radical of shifts for the Piezography 
to handle?

You might check the histogram just before printing. If you see 
any "comb" effect (areas of missing data) whatsoever then Piezography 
could print it as you describe. Although Piezography software is 
capable of producing stunning prints from a great original file, it 
shows no mercy to anything more than small curve or levels 
adjustments. And yes, Piezography software can definitely print a 
posterized print even though it looks fine on your screen. The 
original Piezography was not a color managed system, so what you see 
on your screen is not necessarily what you'll get off your printer. 
The new PiezographyBW ICC system using profiles, on the other hand, 
IS a color managed system so if your equipment is color managed then 
what you see on your screen is exactly what you'll get. A really nice 
feature. Also, the new PiezoICC system now uses the Epson driver 
which is much more forgiving to aggressive curve and levels 
adjustments.

I had the same problem with my 1160 and FS inks and the cone plug in. I've fixed it 
by switching to Quadtone RIP and making my own curves. The cone driver is just not 
accurate enough for skin tones from my experience.

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "petroscans" <chris@p...> 
wrote:

> I've been trying to figure this out; maybe someone can help:
> 
> Mostly I shoot/print still life, landscapes, other inanimate 
> objects.  I've been printing with an Epson 1280 using MIS Full 
> Spectrum inks with the ConeTech Piezography driver for a year now.  
> Terrific results on everything until now.
> 
> I got suckered into doing some student photos at a local private 
> school.  Made the exposures on 35mm TMax 400.  Scan with Nikon Super 
> Coolscan 4000ED.  Print as described above.
> 
> I've noticed some, not all, skin tones get really mottled or 
> posterized in the prints.  Several of the girls have large splotches 
> around eyes and nose.  Also, arms and hands seem to be common spots 
> for this to occur.  The mottling seems to occur in 30-40% grays, but 
> the print darkens them up with the splotching.
> 
> I've tried:  Nozzle check with Head Cleaning (All A-Okay);
> Printing a test gradient from 100% to 0% Gray--looks great!
> I rescanned a couple problem images at 16bit and the problem was 
> still there in the prints.
> 
> Is it possible to make Curves adjustments that look Fine on screen 
> (even at 100%) but contain too radical of shifts for the Piezography 
> to handle?  
> 
> Any other suggestions?  Help?
> 
> Thanks!
> 
> Chris
> http://wwww.petroscans.com