Digital BW, The Print

Roy Harrington wrote:

> The dpi doesn't select the droplet size but does determine what has to be used.
> With 2880x1440dpi there are up to 2880x1440 drops/sq.in.  and it turns out that 
> 4 pl drops gives enough ink to make a full black.  So you use the ultra micro,
> single dot size drops.  For 1440x720 that are 1/4 the number of possible drops so 
> you must use larger drops.  The only thing that makes sense is to use (4,8,20).  That
> way the largest drops can be used for dMax and the smallest can be used in the
> lighter areas and of course the mid size in the middle range.  Note that the smallest
> dot is the same for both cases -- so the light grays will be similar in dots/sq.in.
> in either resolution.   This is probably why 2880dpi is not favored particularly.  It
> takes 4 times as long and the results are "similar".
> 
> If you were to go to 720x720 the 20pl dot would not be large enough 
> for a dMax black so you would need to use (8,20,40) and the lightest
> gray areas would show half as many bigger dots as the above cases.
> 
> So based on the dpi you pick, you must pick a large drop that is big enough to
> give a dMax black.  If it turns out there are smaller dots that can be used together
> with that large dot in a variable dot mode then it make sense to use it.

Roy,

This relates to my QTR trials with the Epson 10000CF. As 
written before the 9000/9500 driver works with the 10000CF and 
with the 9600 driver it will crash. However the 9000 driver 
doesn't have the droplet variation data for the 10000CF (as I 
guessed and more convinced now with your message here) so it 
reaches Dmax at 30% in the calibration ramps. Any chance you 
can do something about it ? Make a trial 10000 driver that I 
can test and report back on?

Ernst

                    --
           Ernst Dinkla


www.pigment-print.com
(         unvollendet         )