Roy,
thank you so much for that clear and informative explanation.
Keith
--- In QuadtoneRIP@yahoogroups.com, Roy Harrington <roy@h...> wrote:
>
> Hi Keith,
>
> There are two basic philosophies with Soft-Proofing and ICC
printing.
>
> The first is where you print without using any color management
> conversions.
> The soft-proof here is to show you on the screen how the image will
> look on the print.
> The assumption is that the driver has some builtin tonal
> characteristics and you are
> just simulating them during soft-proofing. To set up soft-
proofing
> for this you select
> "Preserve Color Numbers" -- this means the numbers in the file go
> directly to the driver.
> The Assign Profile you did doesn't change the numbers in the file
so
> for printing it's
> effectively no change. You "see" a change on the screen because
the
> file-to-screen
> always has color management in effect -- the new profile gives the
> numbers a new meaning
> so they get converted differently for display. If you were
printing
> directly from Photoshop
> it would be like selecting "Same as Source" or "No Color
Management".
> -- your case basically illustrates this mode, the print comes out
> lighter and the
> softproof could be used to show this.
>
> The second philosophy is the more complete mode. Here the idea is
to
> use the
> ICC profile for two functions. First the profile is used for
printing
> so that the color
> management can match and convert the input file profile to the
driver
> profile and make
> the print look as close as possible. Then the same ICC profile can
be
> used for soft-proofing
> to show what differences still exist. For grayscale the main
> difference will be the hue of
> the print. To setup this soft-proofing the "Preserve Color
Numbers" is
> turned off -- its
> assumed that you will print using this same profile. PW and IB try
to
> account for the
> differences between screen b/w and print b/w. To print using a
> profile you must
> Convert-to-Profile rather than Assign-Profile. This will convert
the
> file numbers into the
> print profile space. If you were printing directly from PS this
would
> be the same as selecting a
> print profile in the Print-with-Preview page.
>
> The QTR-Create-ICC could be used in either way but usually in the
> second way.
> But the 2.3.0 version is a gray-only ICC so the soft-proofing won't
> show any difference
> but it is effective as a printing profile. Version 2.3.1 has color
> soft-proofing so should
> give the full second method. There is a problem right now with the
> white-point of this.
>
> Roy
>
> On Saturday, October 15, 2005, at 10:34 PM, fitness2health wrote:
>
> > I am having some problems soft-proofing.
> >
> > My setup is Windows XP, Photoshop CS and an Epson 1270. I have
> > created a curve using QTR v 2.3.10 for Kirkland Photo Paper with
UT-
> > FSN (but using the 3 gray inks only i.e. not using PK). I am
using
> > QTR Gray Lab as my workspace with perpetual intent. I set up an
ICC
> > profile using the QTR-Create-ICC (both from v 2.3.10 and v 2.3 I
> > could not see any difference.).
> >
> > The problem I am having is getting the monitor to match the
output. I
> > load an image and change the image mode to grayscale (I.e. Gray
Lab)
> > from RGB.
> > · If I then "Assign Profile" using the ICC I made with QTR-
> > Create-ICC (in my case QTR-UTFSN-KirkPP-AllGrays), I see a
lightening
> > of the screen image which is then similar to the print.
> > · However, if I set up a Proof Setup Custom using the ICC (QTR-
> > UTFSN-KirkPP-AllGrays), which I do without any image loaded in
> > Photoshop, and check BPC, but not PW or IB, I do not see any
change
> > in the image. BUT, if I check Preserve Color Numbers (which hides
the
> > BPC checkbox) I see the same lightening of the screen image
> > as "Assign Profile".
> >
> > My question therefore is when using soft proof profile should I
use
Show quoted textHide quoted text
> > BPC or Preserve Color Numbers, because it looks like the latter is
> > being used by "Assign Profile"?
> >
> > Any help is hugely appreciated
> >
> > Keith Prue
> >
> > PS. Aside from this I am having great output with QTR.
> >
> >
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> -
> Roy Harrington
> roy@h...
> Black & White Photo Gallery
> http://www.harrington.com
>