Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "benc_1972" 
<ben@...> wrote:
>
> OK, I've kicked off the process of making some curves for UT2 inks 
> with Hahnemuehle Fineart Pearl paper, starting with the Premier 
Semi 
> Gloss curves on Paul's website. First thing - print a stepwedge, 
have 
> a look at it and examine the curves in photoshop.
> 
> The neutral curve looked pretty neutral, the steps between 95% and 
> 70% looking a bit light as best I could judge by comparison to my 
> monitor. I know I could simply do a 'create ICC' at this point and 
> have done with it, but I want to understand...
> 
> So I take a look at the curves. I've read Dirk Hobman's explanation 
> of how to interpret these from the MIS website. I'm rather 
surprised 
> by two things. First, the neutral curves for Eboni ink have a blue 
> curve that is almost flat across the top of the grid. My 
> interpretation of this is that the light grey doesn't get used with 
> this curve. Second, the version of the curves for Photo Black has 
the 
> blue curve dropping to zero at the left-hand end of the grid.
> 
> From Dirk's explanation, I understood that 'all inks at zero' was 
> needed so the Epson driver would know to get the black ink 
working... 
> so where does that leave the Eboni curves? Is the light grey more 
or 
> less redundant? And what tells the driver to bring in the black?
> 
> This is giving me a headache!
> 
> Any help appreciated,
> Ben
>


OK, I've figured out part of it - it's not light grey in the yellow 
position, it's sepia (doh!). Still not sure howe the driver knows to 
turn on the black though!
Ben