QTR-Quadtone RIP

There have been a couple of comments about the 3800 profiles on matte 
paper.
The shadow regions always present compromises for dMax, color accuracy,
and shadow separation and linearity.   All these things tend to 
conflict with each other.   It
appears that tradeoffs I made may be a little different than the Epson 
ABW mode.

Roy

On Wednesday, May 2, 2007, at 05:22  PM, Leping Zha wrote:

> 1. I tried to repost to take care of the ill-reformatted charts,
>    but obviously did not succeed.  Sorry -- multiple identical
>    posts also went into the daily digest.  Anyone really
>    interested in these charts please email me for the original
>    text file.
>
> 2. After several days adjusting, waiting for ink to dry, and
>    remeasuring, I realized Roy's curve settings are basically
>    what we can get.  By raising the K-ink limits to 55-65, and
>    the K-BOOST to 100 I did raise the D-Max a little bit, but
>    not too much.  And more than 75 did not work.  Overlapping
>    the inks did not help either (within the Eye-One's error
>    bars).
>
> 3. Also I found the K/LK/LLK ink ratio Roy used make more sense
>    than the lower ratios from my measurements.  Using my ratios
>    resulted in less linear gray scales (with no linearization).
>    Corrections always work the best when there is not too much
>    to correct.
>
> Thanks for all who responded publicly and privately,
> Leping
>
>
-
Roy Harrington
roy@...
Black & White Photo Gallery
http://www.harrington.com