Digital BW, The Print

Scott wrote:

>     I'm using Jim Nevins curves with FS MIS inks in an 1160.  I 
> continue to have problems with dark images.  After the curve is 
> applied the images print very dark.  If I lighten the image with 
> brightness, contrast or a tonality adjustment, it results in a flat 
> image with blending of the grays, little contrast and a very 
digital 
> look.
>     I did a gray scale stepwedge and created my own curve which was 
> not perfect, but close.  This brought back contrast and more detail 
> to my images, but they still print very dark.

Scott:

Lumped workflows, such as John Woolf's or Jerry Nivins' where the C, 
M, Y position inks are lumped or mixed together in approximate equal 
proportions across the grayscale range, yield essentially a two-tone 
ink system –- black and gray.  These lumped workflows can produce 
fine quality prints, however they are not dotless in the lighter 
tones (especially noticeable under a loupe) and sometimes shows 
vertical banding in the shadow areas.

Partitioned RGB workflows get around this limitation.  An RGB curve 
set is applied to the image and partitions (or assigns) each of the 
four inks to applicable overlapping ranges of grayscale values.  Thus 
the lightest ink prints the lightest portions of the gray scale etc. 
yielding essentially dotless highlights and lighter tones using the 
Epson driver.  Examples of partitioned workflows include those 
developed by Paul Roark, Chris Brandon, and others.  

Hope this helps clear things up for you.

Jeff Randall