Digital BW, The Print

Hans,

You asked:

>Has anyone experience from using MIS UT (Photo black)
>and Pictorico OHT?

>Is the adhesion good enough (without spraying) for making digital negs?

I just printed a 21-step test file onto a Pictorico film with my 1280 and
MIS UT inks with MIS Photo Black.  I used the standard UT80-N (Neutral)
curve, but increased the printing DPI to 2880.

It looks like the pigments are sticking fine (no "dusting", or other obvious
artifacts that I'd associate with lack of adhesion).

However, I have not actually used a negative made this way.

I don't know how to test whether the adhesion is enough for printing.  Every
fingerprint or touch of any RC surface -- digital or wet print technology --
seems to leave some kind of mark.  With the Pictorico film/UT ink
combination, when I rub my finger across the corner of the dark end of the
21-step test strip, it leaves a "fingerprint" or some type of rub mark.  Ink
does not come off onto my finger.  When I try to rub this fingerprint off
with a facial tissue, it feels like it is sticking a bit.  The surface looks
marred, and with backlighting I can see that tiny bits of pigment were
rubbed off.  The tissue does not look to have any significant ink on it,
however.

In viewing the transparency film before the above damage, the limiting
factors of image quality depend on the viewing method.  The film is
extremely sharp.  My 7.2 line-pair/mm resolution target is well separated on
the 360 ppi test file.  One step up, with a 720 ppi test file, the film
clearly separates the horizontal, 1 pixel wide, 14.4 lp/mm resolution test
chart.  The vertical 14.4 lp/mm test is barely separated; it looks more like
a solid bar at any reasonable magnification.  (At normal viewing distance
many consider 5 lp/mm to be the normal limits of what our eyes can
separate.)

This this kind of sharpness, when viewed as a transparency at very close
range or with magnification, this medium shows defects and artifacts that
would not show on a matte print.  The famous Epson "pizza wheel" tracks are
very apparent, for example, and I can see very fine banding.  So, when
viewed as a transparency, I can't say I like what I see.

With a piece of paper behind the film, however, the image quality is quite
good.  In normal viewing -- distance and light -- I think the file quality
would be the limiting factor.  Artifacts are not obvious.  This may be a
closer approximation of what a contact print would look like.  I do not
think the negative would hold up well with magnification, but for large
contact prints, this might be an interesting solution.

I hope this is helpful to you.

Paul
http://www.PaulRoark.com