Digital BW, The Print

From: "Jean-Marc Humbert" <humbertjm@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Monday, March 17, 2003 2:02 AM
Subject: [Digital BW] Re: FS MIS + Piezo


> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, Tim Atherton
> <timatherton@t...> wrote:
> > what's the benefit of using the MIS FS ink with the Piezo software?
> (on the
> > 1160)
>
> Using also a 1160 with MIS FS Neutral and PiezographyBW : best tonal
> range, smoother transisitions than Epson driver together with the
> (excellent by the way) Jeff Randal's curves and of course if you use
> different papers a huge amount of profiles. The biggest issue with
> Piezo is the difficulties to have the prints matching the picture you
> have on the screen (the Jon Cone's method consisting in using a self
> made dot gain curve is rather unprecise).

Jean-Marc,

Try using the method Tyler Boley posted. You will find it in the files
section. In folder:

Files>Image Processing

If you have access to a densitometer you can take readings from printed step
wedges and create pretty accurate curves for soft proofing.

>
> But things are changing: Jon Cone and Piezography are going in the
> next weeks to release a fully new software which is a RIP (see
> www.piezography.com); apparently Epson 1160 will be supported. I
> don't know if MIS inks will be included in Piezo's new package.

Well we haven't seen any of the companies software support the other guy's
inks yet. However, original Piezo, Piezotones, MIS-FS and the Sundance inks
were all blended to achieve the same densities and use the same ink
positions. I would expect that the Conetech software will work best with the
Piezotones and the R9 software will work best with the Sundance inks because
the software was calibrated around these specific inks. From what we have
seen in the past the other inks in this density family will work with the
software but will not be as quite dead on. Certainly worth a try and the
probability of success seems good.

Martin Wesley

> anyone know if I can use the PiezoBW software with this config?
> 
> Thanks,
> Mark

From: "Kevin Gulstene" <kevin@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Monday, March 17, 2003 11:26 PM
Subject: Re: [Digital BW] Re: FS MIS + Piezo


> Martin-
>
> >
> > If you have access to a densitometer you can take readings from
> > printed step
> > wedges and create pretty accurate curves for soft proofing.
>
> Can you elaborate on how you do this?  What do you relate the density
> measurement to?
>

Kevin,

You print out a standard 21-step wedge using the paper, ink and workflow you
want to use. You then measure all the steps in the wedge that correspond to
the adjustment points available in the Custom Dot Gain curve: 2%, 4%, 6%,
8%, 10%, 20%. 30%, 40%, 50%, 60%, 70%, 80% and 90%. There are no values on
the current step wedge for 6% and 8% but you can safely ignore those as the
other 12 points seem to be good enough for soft proofing.

Some spectrophotometers and their software will give you Dot% values
directly. If all you can read is reflectance than you have to calculate
them. This gets a bit thick but you can set it up in a spreadsheet program.

Dot% = (1-10^-(D-Dmin))/(1-(10^-(Dmax-Dmin)))

Where D is the density of the particular patch you measured, Dmin is the
density of paper white and Dmax is the density of pure black.

The equation is this complex because density is a calculated value:

Density = log(1/R)

Where R= Reflectance, a percentage value of the amount of light reflected
from a surface.

I have posted an Excel spreadsheet in Files>Image Processing with some
sample density values I got from a FS step wedge awhile back.

Martin Wesley