Digital BW, The Print

David:

Thanks for the color information, but I was asking a question re: 
this thread on B/W (no hue or saturation just 
luminosity/brightness).  If one was to build from scratch a pure B/W 
profile, am I still off base?  

Jeff Randall


 in Given the 
--- In DigitalBlackandWhiteThePrint@y..., CDTobie@a... wrote:
> 
> In a message dated 5/8/02 3:59:23 PM, jrandall@c... writes:
> 
> >Aren't all the RGB partitioned curves (and the lumped RGB curves 
as 
> >well) really just specific paper/inkset profiles with the color 
> >(grayscale in this case) mapping values stored in three continuous 
> >transfer curves (R,G,B) rather than as descrete values in a color 
> >look-up table? 
> 
> Now heres someone who knows the true difference between 2d curves 
and 3d Look 
> Up Tables! Always nice to find out someone is fluent in this stuff. 
The added 
> advantage of the 3d LUTs are for correcting localized variations 
> (non-linearities) that can't be reached by any one channel. In 
color terms 
> (since its much easier to visualize than the gray inks) this means 
that if 
> the medium saturation orange tones are too dark, or to saturated, 
or too red, 
> that one specific area can be adjusted in an ICC profile, while a 
set of RGB 
> curves could only make changes that would effect all reds or all 
yellows or a 
> given lightness, no matter the exact hue or saturation. 
> 
> C. David Tobie
> Design Cooperative
> CDTobie@d...