Digital BW, The Print

ferdinand_paris wrote:

> Clayton
> 
> I found your web site fascinating and helpful.  Thanks.
> 
> I went to try BO and had a little problem because my workflow is
> different to yours.  I could probably solve this on my own, but as you
> said on your website, sometimes this requires lots of ink, paper and
> time.  I hope you don't mind me asking.
> 
> I print from master images that are RGB.  Each tiff file has a colour
> background layer, and a set of adjustment layers that result in a
> monochome RGB image, tagged as AdobeRGB.  
> 
> I print using Qimage, because it enables me to print from a master
> image, while cropping, sharpening and making other adjusments on the
> fly.  To get neutral prints when using all UC inks, I use QTR.
> 
> My first question is, what ICC settings should I use in Qimage for BO
> when printing my RGB tiffs while using your recommended settings for
> the Epson 2100?
> 
> For my first print I turned ICC off. I was fairly sure that this was
> the equivalent setting in Qimage to match "Same As Source" in PSCS, to
> match your recommended settings. However I got a print that was way
> too light across the entire tonal range.  
> 
> If I've got the printer ICC setting right, what else is wrong with my
> workflow?  Do I need to flatten the image before printing?  Or is it a
> problem with Qimage sending RGB output to the printer for BO, rather
> than a grayscale image?
> 
> Regards
> 
> F_P

I think you need a true BO curve implanted in QTR that will use 
the black channel only to get BO printing from the Qimage-QTR 
workflow. One way or another (greyscale-RGB input, (K separation 
is unlikely in QTR)) as long as QTR uses the curves for all the 
UC channels it will translate any greyscale or RGB image to all 
the channels.

Giving Qimage simple greyscale files to start with may make it 
easier to find what is wrong in the workflow, that Qimage still 
makes RGB files in "print to file" is already a problem.

On lighter prints with Qimage-QTR: Could it be that the RGB print 
to file output of Qimage still gets an extra Lab perceptual 
greyscale curve treatment despite ICM being shut off ?  Or does 
QTR something similar with any RGB grey file dropped at it ? 
That can be checked with files from other sources.  On my Wasatch 
SoftRip the lightness setting of 25% corresponds approx. with the 
Lab value so that change in one file with PS may reveal whether 
it is that percentage lighter.
Related to this: AdobeRGB tagging.  If converted to sRGB with 1.8 
gamma, a tagged file and one untagged, what are the results then 
through the Qimage-QTR route ?

Ernst