Digital BW, The Print

Hello Paul,

>>One question I haven't answered yet is whether a 3rd channel
>>would be any better, given that this printer has just 3.5 pl dots. 
> 
>(It may be 3 pl, but at any rate, the 220 is a very good little 
>printer. Too bad it's no longer made.)

Now I'm not sure about the 3.5.  I had that in my head from somewhere
but tried to look it up and can't find any specs in the manual.  So
I'm really not certain what it is.  If anyone can find this somewhere
please let me know.


 
>My experience so far indicates that adding more channels is only 
>useful to the extent the microbanding is more of a problem...

In this case 2 channels eliminated the banding so I'll let it be.  


>That is, on the 260, straight K only was better than multiple 
>channels of Eboni.  

I'm wondering if the 2KBO approach might work on the 260.  I looked at
one of the 3MK curves and it looks like all three are nearly the same,
all stacked up on one another (all three had same ink limit).  That's
what I began with, but it looked worse than 1K BO.  When I separated
them by changing the ink limits it got better.  Ended up with a 4:1
ink limit ratio for optimum smoothness.  This can be seen in the curve
chart in the article.  


>My work with the 2200 (for purposes of profiling the large format K2
>printers) as well as the 1800 and 260, indicates that QTR's dither,
>particularly at the very beginning, is smoother than Epson's.  Also, 
>one Eboni in the very light tones is better than 2 MK jets firing. 
>That is what is behind the staged or staggered entry points of the 
>MK jets.  

Interesting, I did something similar without realizing the importance
of it.  The secondary curve begins at about 25.  My curves aren't
defined with input numbers like yours, but were created with the
Shadow, Highlight and Gamma settings (back when I tried BO on the
2400).  The resulting shapes are very much like yours.  The final
contrast control is done with the embedded acv curve


>On the 2200, with its 4 pl dot, I use LK + Eboni.  Since the larger 
>dots print cooler, it has allowed me to make a profile for K2 
>printers that uses only LK at first for very smooth highlights, and 
>also a fair amount of LK in the midtones to reduce the graininess of 
>the Eboni there.  

>The 220, of course, could use the same approach I'm using with the 
>2200, and probably make a better print -- as long as medium warm 
>tone is acceptable. 

Understood. Since I prefer not-too-warm I'm quite happy with the
all-Eboni setup.  I like the range of tones it gets with the various
papers (and the tones are really pretty, clear and not muddy looking).
 But it's certainly easy enough for anyone who's interested to try it.

I'm preparing some sample prints (including the 21-step) to go out in
tomorrow's mail.  One of them is on Kayenta.  I'm especially curious
to know how they compare to your 1K 260 prints because the 260 is the
current model.  My R200 won't live forever...


Regards,
Clayton


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