Digital BW, The Print

A recent post from John Dean started my brain spinning.  Could someone help calm my 
thinking?! 

John Dean wrote:

"And he would probably get much better results printing out of greyscale 2.2 with QTR 
rather than trying to use RGB and the Epson print driver by itself."

Considering that I am using a completely digital workflow, including digital capture, is it 
still necessary to convert to graygamma 2.2?  My images are captured RAW and then 
created in ProPhoto from ACR.  Color to B&W conversion is performed with a channels 
layer.  In a zip file that I downloaded from the qtr download site called 
"grayspaceXYZv2.zip" there is a document titled "gray-readme.rtf", and it says,


"In the past when printing to QuadToneRIP in the Print with Preview dialog the Print Space 
was always Same as Source.  This disabled the Photoshop color management system 
during output to QuadToneRIP and the printer.  With soft-proofing it was possible to 
preview what the output would look like.  However you would still have to edit your file to 
take into account the different between the look of profile attached to the image and the 
soft-proof profile.  Which basically means you are editing to a particular paper/ink setup.  
Most of the time this is OK but if you'd like to try a different type of paper such as photo 
paper rather than matte paper you would need to re-edit the image for the new paper.

With the two new generic print profiles the color management system of Photoshop can be 
used the automatically convert between the look on the display, matte paper and photo 
paper.  In other words you just edit to a generic working space profile.  The Photoshop 
color management system converts the data for display and will also now convert for the 
print using perceptual intent and black point compensation –all seamlessly without having 
to even use soft-proofing.  Since QuadToneRIP already has builtin linearized profiles we 
can use two generic ICC profiles to handle both matte and photo papers.

To use this simply, in Print with Preview select a Print Space Profile either Gray Matte Paper 
or Gray Photo Paper rather than Same as Source when you print.   You should also have 
Intent: Perceptual and Black Point Compensation selected."


The document I just quoted uses the expression "Generic working space profile".  
Considering this information, my thinking is that is shouldn't matter if I use a generic 
working space profile that is RGB or gray gamma 2.2.  What difference does it make if I 
manually convert from RGB to graygamma 2.2, or if PS does it for me when it converts 
from RGB to this gray matte paper print space. 

Is my reasoning flawed?

It certainly would be easy to change my workflow and convert to graygamma 2.2 after 
doing my color to black and white conversion.  It's not that I want to eliminate this step.  
I'm just trying to understand what's going on so that I can do or not do the conversion 
because it is needed, not because I am following a recipe like a robot.

Thanks for any insights.

Best.

Josh

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "john dean" 
<deanwork2003@y...> wrote:
> I would never assume that what a monochrome image looks like on a
> screen is the same animal as a print on rag paper. Reading the numbers
> are far more important in regard to tonality, contrast, and density. 
> 
> If he is not using QTR, Bauhaus, or another rip with the 9600 for
> black and white he should be. And he would probably get much better
> results printing out of greyscale 2.2 with QTR rather than trying to
> use RGB and the Epson print driver by itself. Just my thoughts from
> direct experence with this machine.
> 
> John 
> 
>