QTR-Quadtone RIP

Sorry, it's been a long day. Not sure anyone could decode
what I was saying..


> I would just add two things:
> 
> 1st is that almost anything you do gets adjusted
>  ie. undone, by  the linearization, so don't sweat 
> it too much.

fixed punctuation on that one. In general as long
as you pick a reasonable limit it just doesn't matter.
That's why Roy doesn't even offer individual limits
anymore.
 
> 2nd, that said, the adjustments of the linearization 
> assume that adjustments to the ink produce 
> linear changes to the density (to some extent). So, you don't 
> want for example to choose an ink limit that leaves the 
> 65-90 steps practically the same. Even if 90 is better
> than 65. You are better off making it  so that you can 
> see a healthy change in density at each step. The boost on 
> the black will usually get you most if not all of your dmax
> back. 
> 
> The biggest goal is the smoothness of the pre-linearization
> ramp. No flat spots (particularly in 90+ steps).
> 
> hope that helps.
> Costa

The linearization takes whatever you have produced (and
measured with the densitometer) and tries to scale it back
to have the proper (e.g., 2.2 gamma) curve. This might be
something like 1.7, 1.5, 1.4 for the first few values. Imagine
that you have instead, 1.7, 1.6, 1.5. Your values are a too 
high. So the linearization scales back the ink value some
for each. However, imagine that you have your ink limit very
high so that all the steps above 60% look the same. Now if the 
linearization tries to scale back by say 20%, it might have a very
small effect on density, (just as moving back from say the 80%
step to 60% shows only a small difference). So, better to
make sure that the linearization has something to work with-
ie stay in the mostly linear portion of the curve. 

You can use the highlight and shadows adjustments to similar
effect in the step after setting the limits.

hope that is at least slightly more useful.

Costa