Digital BW, The Print

Steve,

You have been of great help in your below reply and I am very 
thankful for it. Please allow me to try to further understand the 
subject since I am still confused...sorry.

In B&W you do not face the color value conversion, you just re-map 
the L* value from L* 0-100 to a printer-paper-ink space say L*17-95. 
But this is done at the curve creation stage and at the printing one 
when you call for the curve in QTR : doesn't this curve apply what we 
can extrapolate as an icm profile (to make it simple in the wording). 
So to convert your file with the grey icm and send the converted file 
to QTR applying the linearized curve should somehow either :

1. double profile : a source L*50 would become L*56 (with a 17-95 
linearized grayscale) converting the file with the icm. And once the 
QTR curve applies it would to re-processed to become about L*61. It 
would be like printing with a destination profile in PS and having 
the EOM driver applying color managment.
This of course can not be.

2. have no effect on the output: the file is well converted but the 
icm interpret the source L50 to a L50 output (only the display values 
but not the output values are converted thus allowing soft proofing) 
and send it to QTR as such that will do the conversion with the curve.

So in terms of purely improving the output, the grey icc is not a 
must. It is only great help in terms of editing your file in PS so 
you get a perfect match between displayed image and printed one with 
from my understanding the limitation of BP (which I understood is not 
the true paper Black but a perfect one).

Understanding this may not improve QTR users' prints (you are said to 
convert with the grey icm before printing : do it and shut up!!!), 
but it may prevent some mishandling of the soft.

Thanks.

Olivier