Re: Two tricolor prints curvers in Photoshop

[Katharine Thayer <kthayer@pacifier.com>]

On Sep 26, 2007, at 11:38 AM, Marek Matusz wrote:
> This is something that I watch for making separations. Are there  
> places in the print that require clean two color mixes and is the  
> color separation negative of the third primary sufficently dense to  
> block the third color layer
On Sep 26, 2007, at 4:47 PM, Marek Matusz wrote:

> This is FANTASTIC. After years of battling color shifts, using  
> masks, etc to find such a simple solution. Evry curve results in a  
> perfect color balance. Whats more curves can be applied to RGB  
> components separeately still with perfect color balance. Michael,  
> I'll buy a beer next time you are in town.
Thanks, Marek and Michael.  It seems like you're approaching closer  
to something like the three-dimensional calibration I was saying we  
need for tricolor gum, but lots easier than what I was imagining.

In the meantime I had an idea that helped me understand my problem:   
I made a copy of the greyscale inverted red (cyan) channel, added a  
color layer to it, then turned that back into greyscale and looked at  
it side by side with the original greyscale.  That visual sxs helped  
me grasp  the relationship between negative color and tonality  
(uncomplicated by curves)  better than  weeks of  staring at numbers  
and curves and calibration charts,  and I'm a number person, for  
heavens' sake.
Katharine