QTR-Quadtone RIP

Hi,

I was printing on Moab Bright White using curves for Epson Velvet, standard inks, three curves  I not concerned about precise results at this time.  Anyway I found that horizontal banding, bands about 1/8-1/4" appeared across the entire image.  I tried changing to unidirectional, various dithers but there was no change.  So then I switched to the Epson Advanced B&W driver and had no problems -- a perfect image.  What's going on?

Jason

Is this on Windows?

If so, I've found that the Epson driver is much more tolerant of blocked 
or deflected inkjets than the ghostscript driver that underlies QTR. 
(Except when printing close to the leading and trailing edges of the 
paper, when sometimes you'll see a similar pattern even with the Epson 
driver)

Jason wrote:
>  
> ... Anyway I found that horizontal banding, bands about 1/8-1/4" 
> appeared across the entire image. I tried changing to unidirectional, 
> various dithers but there was no change. So then I switched to the Epson 
> Advanced B&W driver and had no problems -- a perfect image. What's going on?
> 
> Jason

-- 
mike finley photography
fine art photography and website construction
http://mypicks.efikim.co.uk
http://www.mikefinley.co.uk
http://www.roguegenecollective.com/Mike_Finley.html
http://www.efikim.co.uk

The problem is on a Mac with 10.5.  I've been turning out piles of  
defect-free images with the Epson driver since I observed the problem  
with QTR.  The width of the banding seems to be related to the size of  
the print head; it's not subtle at all.   You suggested that the Epson  
driver is more forgiving about print head clogs.  If this is true,  
what is the explanation for this? I'll do more experiments to see if  
it's paper specific.  Could it be?  Has anyone had direct experience  
with this problem on OS X with a R2400?

Jason

----------------------------
jason@...
http://www.jasonwinshell.com



[Non-text portions of this message have been removed]

Jason Winshell wrote:
>  
> ... The width of the banding seems to be related to the size of
> the print head; it's not subtle at all. 

That matches what I saw on Windows.

> You suggested that the Epson
> driver is more forgiving about print head clogs. If this is true,
> what is the explanation for this? ...

My guess is that the Epson driver uses every jet on each line of 
printing as it goes up the page, while the dither that QTR uses uses 
fewer jets (possibly only one or two) and so the impact of one misfiring 
is much greater. (With the Epson driver you can see the image gaining 
density as it moves past the print head if you lift the lid and hold in 
the front while printing)

-- 
mike finley photography
fine art photography and website construction
http://mypicks.efikim.co.uk
http://www.mikefinley.co.uk
http://www.roguegenecollective.com/Mike_Finley.html
http://www.efikim.co.uk

I don't know your printer model, but in my experience, any driver or print system that utilizes individual inks to their maximum advantage, usually for B&W, will reveal more potential ink delivery problems than other systems that combine more inks and dot sizes to form grays or individual tones.
The ABW driver seems to use all three blacks and dot sizes in an unusual fashion down the scale, and mix in the color inks as well. While the results are mechanically smooth, and reduce tech support issues dramatically for them (after all, the printers are VERY aggressively priced, therefore what precision we do wind up getting from them is pretty remarkable), this sacrifices in dottiness and resolution.
So, a more photographically superior method for B&W that uses individual inks to their full usefulness, the light blacks in particular, shows each of those channels nearly "naked" in parts of the scale with very low percentages (sometimes none) of other inks dithered in.
This demands higher precision mechanical performance from each and every ink, and nozzle. So clogs or inadequate ink delivery, and alignment issues, are all critical to avoid banding. In fact, some printers will simply not perform well enough for highest quality B&W.

QTR is not banding, as opposed to ABW, the printer is, and QTR is showing it to you while ABW is masking it. Hope that makes sense. 

So make sure nozzle checks and alignment are dead perfect, and paper feed is not slipping with fine art papers... etc etc.
Most of you don't remember the days of going through multiple 3000s and 1160s to find one good enough for advanced grayscale printing methods... lucky kids.
Hope that helps.
Tyler

--- In QuadtoneRIP@yahoogroups.com, "Jason" <jason_winshell@...> wrote:

>
> Hi,
> 
> I was printing on Moab Bright White using curves for Epson Velvet, standard inks, three curves  I not concerned about precise results at this time.  Anyway I found that horizontal banding, bands about 1/8-1/4" appeared across the entire image.  I tried changing to unidirectional, various dithers but there was no change.  So then I switched to the Epson Advanced B&W driver and had no problems -- a perfect image.  What's going on?
> 
> Jason
>

tried to send before, never showed up, please forgive possible double post...


I don't know your printer model personally, but in my experience, any driver or print system that utilizes individual inks to their maximum advantage, usually for B&W, will reveal more potential ink delivery problems than other systems that combine more inks and dot sizes to form grays or individual tones.
The ABW driver seems to use all three blacks and dot sizes in an unusual fashion down the scale, and mix in the color inks as well. While the results are mechanically smooth, and reduce tech support issues dramatically for them (after all, the printers are VERY aggressively priced, therefore what precision we do wind up getting from them is pretty remarkable), this sacrifices in dottiness and resolution.
So, a more photographically superior method for B&W that uses individual inks to their full usefulness, the light blacks in particular, shows each of those channels nearly "naked" in parts of the scale with very low percentages (sometimes none) of other inks dithered in.
This demands higher precision mechanical performance from each and every ink, and nozzle. So clogs or inadequate ink delivery, and alignment issues, are all critical to avoid banding. In fact, some printers will simply not perform well enough for highest quality B&W.

QTR is not banding, as opposed to ABW, the printer is, and QTR is showing it to you while ABW is masking it. Hope that makes sense. 

So make sure nozzle checks and alignment are dead perfect, and paper feed is not slipping with fine art papers... etc etc.
Most of you don't remember the days of going through multiple 3000s and 1160s to find one good enough for advanced grayscale printing methods... lucky kids.
Hope that helps.
Tyler

--- In QuadtoneRIP@yahoogroups.com, "Jason" <jason_winshell@...> wrote:

>
> Hi,
> 
> I was printing on Moab Bright White using curves for Epson Velvet, standard inks, three curves  I not concerned about precise results at this time.  Anyway I found that horizontal banding, bands about 1/8-1/4" appeared across the entire image.  I tried changing to unidirectional, various dithers but there was no change.  So then I switched to the Epson Advanced B&W driver and had no problems -- a perfect image.  What's going on?
> 
> Jason
>