Digital BW, The Print

Hello Ernst,

>I'm still convinced that much of those BO banding issues can be 
>diminshed to zero if the black ink can be squirted from many 
>nozzles. 

I can't argue with the idea, not having tried it, but I wonder,
because last summer when I did the analysis of the tech print exchange
one of the things I graded on was dither banding, and even included a
report for each print on which sections of the ramp it appeared. 
Every system was represented in that exchange and they all had it to
some degree (one Septone print had none, but others did have some).  I
have also seen it in BW prints from my 2200 made with the full UC ink
set. 

>With QTR it must be possible to use all the heads of say a C84 
>with black and reduce the amount of ink on all heads where 
>needed. 

In a recent print exchange I received a QTR/Grayscale print that has
some of the worst dither banding I've seen.  So it would seem that
having all nozzles firing doesn't seem to be related...but it was also
done with an "Epson Photo EX" - I don't know what that is, could it
have caused it?  

Flash! - I just now rec'd in the mail a QTR-XP/2200/UC print that has
some very minor DB.


>the 4000 does a good job with its 180 nozzles 

There also seems to be two different kinds of DB.  Carl Schofield sent
me some 4000 BO prints that had no DB throughout the print (covering
all Zones) except for a barely visible amount (with 8x loupe) about
3/4 inch along one end (either the start or the end of the print, but
only on one end).  This DB also crosses all Zones, which means it is
more likely from a physical cause such as paper feed, etc.  Much DB
appears only in certain Zones, which would seem to be software
related.

I also received a 4000 BO print from someone else that has quite a
lot.   I just went back through a dozen prints from a BO exchange and
found two without any DB (both from 2200s) and three more with
miniscule amounts in a few places.

At least we know it's possible not to have any dither banding with BO.
What do you make of all this?

Regards,
Clayton


Info on black and white digital printing at    
http://www.cjcom.net/digiprnarts.htm