Digital BW, The Print

In a message dated 5/9/02 11:28:33 AM, jrandall@... writes:

>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?  

But they are not black and white profiles... they are always color profiles, 
with varying hues and saturations in the target patches, and expectations of 
hue and saturation values coming back... and the resulting profiles are a 
series of Color Lookup Tables... so fooling them with a small gamut works 
better with some software than others, and replacing the expected colors with 
unrelated grays of varying brightness values will cause the software to 
process things like "lets see, I asked for bright red, which of these eight 
hunderd gray patches is the reddest?" which can actually be of value for 
previewing if you are using a variable tone ink set, but is quite limited for 
a neutral gray set. It would just print most of the possible combinations of 
of inks, map which of them best define which grays from the chart, and line 
them up in that order. This could have some unexcepted changes in there as it 
decides that the best medium gray is from one pair of inks, and the next step 
darker is better printed from an entirely different cart or carts.

C. David Tobie
Design Cooperative
CDTobie@...