QTR-Quadtone RIP

--- In QuadtoneRIP@yahoogroups.com, "Joost Horsten" <j.h.j.h@...> wrote:

> But why not simply have three sliders, one for each curve, giving the 
> relative weight of each curve, just like the channel mixer in 
> Photoshop? (would be nice though if the weights automically be 
> balanced to 100%, a feature I miss in PS). The result would be just 
> the weighted average of the three curves. Just like the current 
> slider is the weighted average between two curves. The mathematics of 
> this 3 curve averaging is trivial. What should this 
> color engine do more than that? Do I miss something? 

Now I have given this some more thought I think I understand what you 
mean. I think we have two different objectives, yours being more 
advanced than mine.

My approach is that of a painter, having a choice of pigments (curves), 
putting some together in certain quantities and looks to end result. If 
that is not right yet, you change the quantities and try again. 

My interpretation of your approach is that you want to define a colour 
point in advance and have the relative contributions of the primes be 
determined by the system.

In my approach, the simple slider approach would suffice (although now 
I think it over, the number of sliders is not fundamentally limited to 
three as I stated earlier). In your approach (as interprete it), which 
is much more sophisticated, one needs a color engine indeed.

I'd love use to your color-engine approach, but for my now my desires 
are more modest ;-). Just a set of sliders and experimenting with the 
result would already be great.

To give some idea how I think to bring some system in this experimental 
approach. First mix two of the "primaries" to get the hue you desire, 
than add as a third curve a neutral curve to control the saturation of 
the mix. This is more or less how I mix my paints & inks in one of my 
other lifes as painter/printmaker.  

Do we converge in our thinking? Or do I still miss the point?

Joost