QTR-Quadtone RIP

Gary,

If this is a density shift with feathered edges and is found ONLY in 
the solid black areas, then it is a common problem with the gimp 
driver which QTR utilizes.  I have experienced this a number of 
times.  Adding about 2% noise to the image tends to eliminate this 
feathered banding.  I usually duplicate the final image and run th 
noise filter through a blurred mask to limit it to the black areas.  
The blur helps avoid any lines of demarcation so it isn't obvious.  I 
haven't tested it, but I have heard that adding just a little of a 
2nd ink to pure black end of the profile can also eliminate the 
effect.

I have recently been building 2880 dpi profiles and haven't yet 
noticed this effect at the higher dpi.  Not sure if it will surface 
or not.  

If you are seeing this problem in areas other than just the pure 
black regions, it probably is a different issue, which I have not 
experienced.  

Lou

--- In QuadtoneRIP@yahoogroups.com, "photog0946" <gnickzone@...> 
wrote:
>
> HELLO GROUP,
> 
> I have had some very good results with QTR since I purchased it
> approximately 18 months ago. However, I have also experienced some
> problems along the way. On occasion I have noticed what I can only
> describe as a sort of "Splotching" effect in some prints. What this
> amounts to is a rather irregular pattern of increased density. 
Almost
> as if I were to take a brush and paint in more density in a 
haphazard
> way. Of course this effect will always render the print unusable. 
The
> other part of this anomaly is that when I do a reprint, it will
> sometimes not appear at all, or it will manifest itself in a
> completely different area of the image. Yesterday I encountered a
> problem I haven't noticed for a while, although it has been there on
> occasion. I was trying to print an 11x14 Warm Sepia. Down one side 
and
> not as noticeably on the other side was what I would describe as a
> sort of banding. The "bands", again, were all of a plus density
> nature, very diffused, and approximately 1/8th of an inch in width. 
I
> did 2 prints with basically the same results. I then printed the 
image
> through the Epson driver and had no problem at all. Of course I
> couldn't obtain the effect was trying to achieve with QTR, but at
> least I did finally get a print.  
> 
> Let me clarify one thing. These problems are happening in what seems
> to be a totally random way. Both while trying to achieve a neutral
> print and while utilizing one or more of "color" curves provided. 
And
> again, as I mentioned previously, the second and third prints from 
the
> same file may or may not show the problem. I am using a 7600 with MK
> and I always make sure the nozzles are clear before printing. All of
> these prints are done on Epson Enhanced Matte Paper. I have no 
problem
> with the native Epson driver, either when printing color or a 
neutral
> image. I very much like the possibilities provided with QTR and the
> neutrality of the images, but if I can't find a solution to this
> situation, I may have to take it out of my workflow. I DO NOT want 
to
> do that, so I hope someone will be able to offer a bit of advice
> concerning this problem.
> 
> Thank you,
> Gary
>