QTR-Quadtone RIP

Thanks to both Toms (Moore and Husband).  Apart from the fact that I 
understand what is going on slightly more, I have use advice from 
both to fine tune my workflow.  I now convert to RGB-LAB in CS2 when 
working on the original image (just after conversion to B&W) and 
soft proof using QTR-RGB Matte.  My final output file in Qimage is 
saved with profile QTR-RGB Matte and the final print matches much 
closer what I see on screen than previously! 

Another quesion this time re soft proofing.  Should one normally use 
the "Simulate Black Ink" option?  In my case I find the final print 
output is somewhere between the two (i.e. simulate on or simulate 
off) in terms of density of blacks.

Thanks again,

John

--- In QuadtoneRIP@yahoogroups.com, "Tom Moore" <r.t.moore@r...> 
wrote:
>
> John
> 
> I'm not sure why you are opening the Qimage output file in 
Photoshop -
> perhaps it's just curiosity. In any event, I don't think QTR looks 
at any
> embedded ICC profile, if present. 
> 
> Here's how I understand these matters.
> 
> If you "Assign" a profile to an image, it would not affect how QTR 
would
> print that image, although it would likely change the way you see 
the image
> on your monitor. That is because you are not changing the RGB 
values of each
> pixel (or gray value is grayscale) but you may be changing the 
meaning of
> these values. 
> 
> However, if you "Convert" an image to an ICC profile, then its 
appearance
> would not change on your monitor, but it would likely change how 
the printed
> image appears. That is because the RGB values for each pixel would 
likely be
> changed but the newly associated ICC profile would preserve its 
appearance
> on the monitor. However, since QTR does not look at ICC profiles, 
the
> modified RGB values would change the way the image is printed.
> 
> Here's how I use this info in my workflow:
> 
> 1.	when working up an image in PS, I convert it to Gray-LAB (for
> grayscale) or RGB-LAB (for an RGB image) early in the process. I 
don't think
> it matters at this point whether I use Assign or Convert as long 
as the
> image has one of the LAB (from the QuadToneRIP\Icc folder) profiles
> assigned. You can convert/assign to the LAB profile at any time. I 
do it
> early in the process because doing so can have significant effect 
on the
> image histogram, and I think it's better to do it before I adjust 
the tonal
> range pf the image, which I do early in the manipulation process.
> 
> 2.	If the curves I intend to use for printing have an 
associated ICC
> profile, I use this profile with the PS soft proof feature to 
preview how my
> image's tonal range will be mapped onto the tonal range available 
for the
> paper/ink combination for those curves. Otherwise I could use the 
generic
> profiles for matte paper (Gray-Matte or RGB-Matte) or photo paper
> (Gray-Photo or RGB-Photo).
> 
> 3. Currently, I print from PS by saving a flattened tiff file once 
I am
> happy with the image. I'm not sure of the process with Qimage. I 
currently
> have the demo to see how beneficial it might be.
> 
> Tom Moore
> 
> > -----Original Message-----
> > From: QuadtoneRIP@yahoogroups.com 
[mailto:QuadtoneRIP@yahoogroups.com] On
> > Behalf Of John Wood
> > Sent: Sunday, October 30, 2005 2:10 PM
> > To: QuadtoneRIP@yahoogroups.com
> > Subject: [QuadtoneRIP] Confusion regarding Profiles and QTR
> > 
> > Hi.
> > 
> > I'm really confused about a particular point (well, in fact I'm
> > confused about a load of things relating to QTR, profiles, Dmax, 
L*,
> > etc etc etc - but this is the first question on my list!!!).
> > Grateful for any help!
> > 
> > I have been playing around with QTR on Windows and my Epson 2200 
for
> > a few weeks.  I use CS2 and ConvertToB&WPro V3 for image
> > manipulation (usually limited to dodging & burning), Qimage 
(print
> > to file) for final print interpolation and sharpening and
> > the "canned" QTR EEH curves for final printing on EEH (usually 
75%
> > cool 25% warm works well for me).
> > 
> > The print output file produced by Qimage does not have an 
embedded
> > profile (when I open the file from CS2 it asks me if I want to
> > assign a profile).  What should I do at this point - should I 
assign
> > a profile before printing or not?  And if I do, which profile 
should
> > I assign - Adobe RGB, Dot Gain 20%, or one of the QTR profiles?  
Or
> > does this not matter one iota to QTR?
> > 
> > I've tried to find the answer in the manuals and this forum but 
I'm
> > hopelessly uneducated in this whole subject and totally 
overwhelmed
> > by the jargon!
> > 
> > Thanks for any advice!
> > 
> > John Wood
>