Digital BW, The Print

I've recently installed Roy Harrington's QuadTone Rip 2.0

Running set-up tests with..
 PizeoTone selenium inks
 Epson Matt Heavyweight [A3]
 Quad Tone Rip 2.0


WOW - The results are stunning!,  However the photographer whose work I've
been printing commented on what appeared to be slight 'tonal' banding
running down the length of the print. Bands are about 30-35mm apart.

I checked prints made from the same file printed using the Cone driver - no
banding. 

While we were looking at the print to see what it was I Turned the print
over and we could see the same banding pattern on the back of the print!  On
closer inspection we saw the print paper (Epson MHW) had *very* small but
regularly spaced 30-35mm wide corrugations running down the entire length of
the print. These corrugations are easier to feel than to see directly.

The corrugations are confined to just the printed area.
They are also slightly deeper where the ink lay-down is heavier.
Print paper is definitely flat before it's printed.
I have checked all the other prints made with QTR 2 and found they too have
corrugated the paper in the print area.

We found that the appearance of 'tonal banding' of the print disappears when
the print paper is bent into a strong curve in such a way as to flatten the
corrugations.


My guess is there something about the way ink is being laid down by QTR 2
that¹s causing the paper to swell in a regular pattern.


Regards
Peter Miles






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Message: 22
   Date: Sun, 02 Nov 2003 03:01:42 -0000
   From: "candlefarmer" <yahoo@robeybaur.org>
Subject: Vertical banding with QTR 2

>I've recently started experimenting with the Harrington Quadtone RIP v2. I'm
using the latest beta on an Epson 2200 with the standard Epson inks. Generally
the results are outstanding but I continue to have one show-stopper problem:
vertical banding in dark areas of the print. This seems to be specific to the
QTR RIP - the same image printed using the epson driver shows no such banding.

>It seems to be independent of resolution. I typically use 720x720 but see it in
higher resolutions also.

>I originally thought that the banding was due to excessive ink in dark areas. I
tried lowering the ink limit but the banding remains.

>I've posted an example here:

>http://home.comcast.net/~baur/banding.html

>Is this something others have seen? Any help in taming this would be
appreciated. (I'm trying to get a couple of things printed for a show and this
is driving me batty.)