Question For Those Who Use Quadtone Rip (Roy Harrington's QTR)

[Brian Ellis]

I use an Epson 3800 printer with Epson inks and print on a variety of papers, mostly matte and mostly Epson lately. I've been using QTR for b&w printing ever since it first became available years ago, always liked it, never had a problem. But lately when I make a b&w print with it I get very noticeable vertical banding (i.e. banding from top to bottom of a photograph in landscape format) When I switch to Advanced B&W in Epson's printer software I get no banding. Anyone have any idea why I'd get banding with QTR and not with Advanced B&W?

[SAShruby]

Hi Brian,

I think you'll be better off to ask this Roy Harrington directly at quadtone@harrington.com

[Tyler Boley]

QTR does a better job of isolating and utilizing which particular ink is used for what, to print the grayscale image. ABW uses a more randomized combination of the inks and dot sizes. You can see this pretty easily under a loupe. The advantage being, individual ink/dot size/nozzle performance in particular parts of the scale are masked somewhat by the others. The disadvantage is a somewhat noisier image structure and less hue control.
In QTR, best example being provided "warm" curves which use no color inks, tones progress from white to black using each appropriate light black ink only, to the next darker, and then to black. 2880 only uses smallest dots, but 1440 and others each ink also has 3 dot sizes it progresses through.
Any of of these inks, even down to a particular dot size, can have mechanically less than optimal placement or other delivery problem. Since it's far less masked by the presence of other inks, these problems become much more visible using QTR, even using other curves for hue that add some color inks to that basic underlying structure of k and lk inks.
That is likely the why, the how to fix is more important though of course, and all the usual stuff you know applies, perfect nozzle checks, alignments, clean paper feed, etc, beyond that it can get hard to find, sometimes even a bad cartridge.. I hope others more familiar with your model than I pitch in, and of course ask on the QTR yahoo list.
Tyler

[Brian Ellis]

Thanks for the responses, particularly Tyler's. I'll try the QTR Yahoo list too but I've always had trouble with the way that forum is set up by Yahoo.

[sanking]

Thanks for the responses, particularly Tyler's. I'll try the QTR Yahoo list too but I've always had trouble with the way that forum is set up by Yahoo.

Tyler has identified why banding could happen with QTR and not with the Epson driver. However, if you have been using the printer with QTR for some years with the same QTR and media setting the most likely cause of vertical banding is a misaligned head. Run a nozzle check to make sure there are no clogged nozzles. If your nozzle check is good run an automatic head alignment routine. If this does not solve the problem adjust your setting in QTR. I recommend 2880 dpi and uni-directional printing.

A worst case scenario is that the head itself is going bad, in which case there is no solution for the problem of banding other than replace the head.

Sandy

[Brian Ellis]

Thanks Sandy, I've run a nozzle check and I think a head alignment. The nozzle check was fine except for maybe 3 or 4 small spaces that I didn't think would matter (and that don't when I print color or b&w with Advanced B&W). But just to be sure I'll run them again. I haven't been printing at 2880, I've always used 1440, I thought that was what Roy suggested but maybe not. I'll try 2880 to see if it makes a difference. I've thought about the head, the printer will be 7 years old this March but my other Epson printers have lasted much longer than that (my old 1280 that my wife still uses must be going on 12 years) without needing a new head so hopefully it's not that.

In any event, thanks for the response.

[Tyler Boley]

Brian, 3 or 4 small spaces matter!!! Nozzle checks need to be perfect, particularly using QTR. Better make sure that is right before looking into more serious possible causes. The first issue is getting back to where you were...
Tyler

[Alex Ramsay]

I'm also having an issue with a 3800 and QTR - for various reasons I haven't made a print with QTR for a long time, and find that now I've started again I can see noticeable 'stippling' in areas of continuous tone. This is much less visible on the same print made through the normal Epson driver, ICC profile etc. I'm using QTR 2.6, OS 10.4, printing on Gold Fibre Silk using the Silver Rag curves as I don't have the GFS curves available. Is this usual, and can anything be done about it?
Many thanks,
Alex

[Tyler Boley]

I'm also having an issue with a 3800 and QTR - for various reasons I haven't made a print with QTR for a long time, and find that now I've started again I can see noticeable 'stippling' in areas of continuous tone. This is much less visible on the same print made through the normal Epson driver, ICC profile etc. I'm using QTR 2.6, OS 10.4, printing on Gold Fibre Silk using the Silver Rag curves as I don't have the GFS curves available. Is this usual, and can anything be done about it?
Many thanks,
Alex

all I can suggest is that perfect nozzle checks, and head alignment, are vital for this kind of printing. There simply no other way.

http://theagnosticprint.org/nozzles/

if everything is perfect and there are still problems, I'd see what kind of feedback you can get at the QTR forum

[Alex Ramsay]

all I can suggest is that perfect nozzle checks, and head alignment, are vital for this kind of printing. There simply no other way.

http://theagnosticprint.org/nozzles/

if everything is perfect and there are still problems, I'd see what kind of feedback you can get at the QTR forum

Thanks Tyler - I'll do a nozzle check, of course, but the prints that I do through the standard Epson driver do not display this effect - continuous-tone areas appear perfectly smooth by cpmparison, so it seems like a QTR issue to me.

Alex