Digital BW, The Print

Roy Harrington wrote:
> 
> 
> I've added a set of the same basic Lab and Printing profiles that have
> been changed to RGB format.   These should be used for printing 
> using Qimage.  Set the printer output icc profile to one of the rgb profiles.
> I'm not positive how to change the file profile to RGB Lab in Qimage but it
> works fine in Photoshop.   
> 
> Note that the RGB Lab space is a true RGB space but it has a transfer function
> with linear Luminosity rather than a Gamma transfer function.   It is not a
> space with an L, a, & b channel.  It might be interesting to use this for color work.
> 
> Roy

Roy,

I have tried all kinds of programs with all the 6 QTR (RGB +
Gray) profiles on XP and 2000pro and one way or another I get
very different appearances in the menus. The profile
installation order may have an influence. I know, there's no
logic in that.

Done so far:
Photoshop CS + Picture Window Pro on W2000pro, Photoshop
Elements and Qimage on XP. Could try Photopaint 9 but that one
isn't installed right now.

Both Picture Window Pro and Qimage are based on LCMS  open
source but they do not behave similar.

One thing for sure is that Qimage doesn't show QTR
RGB Lab in the color spaces choices menu on XP. However it
appears in the monitor and printer profile choices like the
other 5 (RGB +GRAY) profiles do. Photoshop Elements does the
same but its black box approach defaults to Adobe RGB (in
advanced CM mode) as the space so I can't tell whether it
actually notices the QTR RGB Lab space profile. No chance to
select another space AFAIK.

Had several meltdowns of Qimage, some with the message that
lcms couldn't cope with the profile while Qimage was
processing a print file.

The only way it seems to work is by making in PS a greyscale
RGB file with QTR RGB Lab embedded and loading that file in
Qimage, printing it to file with the QTR RGB Matte or Gloss
printer profile. All dry trials as I can't run QTR right now
with the Ultratone inks in the "wrong" ink channels. A true
greyscale Tiff with QTR Gray Lab embedded and printed the same
way doesn't work with the QTR RGB printer profiles. It runs
but the processed tiff shows a lot of black..

Ernst